Embrace the comforting flavors of a bygone era with these delightful Old-Fashioned Amish Rhubarb Oatmeal Crumb Bars. This recipe offers a beautiful balance of sweet and tart, showcasing the vibrant tang of fresh rhubarb nestled between two generous layers of wholesome, buttery oat crumble. It’s an instant classic, easy to prepare, and promises to bring warmth and joy to any occasion. If you’re looking for a homemade treat that evokes rustic charm and irresistible flavor, these Amish Oatmeal Rhubarb Bars are an absolute must-try.

Why You’ll Love These Old-Fashioned Amish Rhubarb Oatmeal Crumb Bars

These bars are more than just a dessert; they are an experience. Here’s why they’re destined to become a staple in your recipe collection:

Perfect Harmony of Flavors: The star of the show, rhubarb, delivers a bright, tangy kick that is beautifully mellowed by the sweetness of the oat crumble. It’s a delightful dance for your taste buds.
Irresistible Texture: You get the best of both worlds – a tender, gooey rhubarb filling contrasted with a hearty, slightly chewy, and perfectly crumbly oat topping and base.
Wholesome Comfort: Made with simple, honest ingredients like rolled oats and fresh rhubarb, these bars offer a wholesome, homemade feel that’s incredibly satisfying.
Versatile Treat: While perfect as a rustic dessert, these bars also make a lovely breakfast companion, a satisfying afternoon snack, or a delightful addition to a brunch spread.
Easy to Make: With straightforward steps and readily available ingredients, even novice bakers can achieve spectacular results.

Ingredients & Substitutions

Ingredients for Old-Fashioned Amish Rhubarb Oatmeal Crumb Bars: Sweet & Tart Perfection

Crafting these delicious bars requires a few simple ingredients, easily found in any pantry or grocery store.

For the Crumb Topping and Base:

All-purpose flour: Provides structure to the crumble.
Rolled oats (old-fashioned): Essential for the characteristic texture and wholesome flavor. Avoid instant or quick oats, as they will yield a different texture.
Granulated sugar & Light brown sugar: A combination that provides sweetness and a hint of molasses depth.
Baking powder: Adds a little lift to the crumb.
Ground cinnamon: Imparts a warm, aromatic spice that beautifully complements the rhubarb. For an extra hint of warmth, consider adding a pinch of nutmeg or cardamom to the crumb mixture.
Salt: Balances the sweetness and enhances all the flavors.
Unsalted butter: Cold and cut into pieces, it creates the perfect crumbly texture. Using cold butter is crucial for a flaky, tender crumble.

For the Rhubarb Filling:

Fresh rhubarb stalks: The star ingredient, providing that signature sweet and tart flavor. For best results, use fresh, firm rhubarb. If using frozen rhubarb, there’s no need to thaw it; simply toss it directly with the sugar and cornstarch, and be prepared to bake a few minutes longer.
Granulated sugar: Balances the tartness of the rhubarb.
Cornstarch: Acts as a thickening agent, ensuring a perfectly set filling.
Lemon juice: Brightens the flavor of the rhubarb and adds an extra layer of tang.
Vanilla extract: A touch of vanilla enhances the overall sweetness and aroma of the filling.

Optional Additions:

A half cup of chopped walnuts or pecans can be added to the crumb topping for extra crunch and nutty flavor.

How to Make Old-Fashioned Amish Rhubarb Oatmeal Crumb Bars

Making these delightful bars is a simple process that yields incredibly satisfying results.

Step-by-Step Instructions:

Preheat and Prepare: Preheat your oven to 375°F (190°C). Grease and flour a 9×13 inch baking pan, or line it with parchment paper, leaving an overhang on the sides for easy removal.
Craft the Crumb: In a large bowl, whisk together the flour, rolled oats, granulated sugar, brown sugar, baking powder, cinnamon, and salt. Cut in the cold butter using a pastry blender, two knives, or your fingertips until the mixture resembles coarse crumbs with some larger pea-sized pieces. Reserve about 1.5 cups of this mixture for the topping later.
Bake the Base: Press the remaining crumb mixture evenly into the bottom of the prepared baking pan. Bake this base for 10-12 minutes, or until it’s lightly golden. While the base is baking, move on to preparing the rhubarb filling.
Prepare the Filling: In a medium bowl, combine the chopped rhubarb, granulated sugar, cornstarch, and lemon juice. Stir gently to coat the rhubarb evenly. The cornstarch is key here, as it will help thicken the filling as it bakes, preventing a watery consistency.
Assemble and Layer: Once the base is lightly baked, carefully remove the pan from the oven. Evenly spread the rhubarb filling over the warm crust. Drizzle the vanilla extract over the rhubarb layer for an extra touch of aroma and flavor.
Top and Finish Baking: Sprinkle the reserved crumb topping evenly over the rhubarb filling. Return the pan to the oven and bake for an additional 30-35 minutes, or until the topping is beautifully golden brown and the rhubarb filling is bubbly and tender when poked with a knife.
Cool Completely: This step is critical! Remove the pan from the oven and let the bars cool completely on a wire rack before cutting. This cooling period, typically 2-3 hours, allows the filling to set properly and ensures clean, neat cuts.
Cut and Serve: Once thoroughly cooled, lift the bars out of the pan using the parchment paper overhang and cut them into squares. Serve and enjoy!

Tips for Success

Achieving perfect bars every time is easy with these helpful tips:

Cold Butter is Key: Ensure your butter is very cold when cutting it into the dry ingredients for the crumb. This creates pockets of butter that melt during baking, resulting in a tender, flaky crumb.
Don’t Overmix: When making the crumb, mix just until the butter is incorporated and the mixture forms coarse crumbs. Overmixing can lead to a tough crust.
Cool Completely: We can’t stress this enough! Allowing the bars to cool completely is essential. If you cut them while warm, the filling will be too soft and will ooze out, and the bars won’t hold their shape.
Adjust Sweetness (Carefully): Rhubarb’s tartness can vary. While the recipe is balanced, if your rhubarb is exceptionally tart, you might add an extra tablespoon or two of sugar to the filling, tasting a small piece (raw rhubarb is very tart, so use your judgment).
Use Parchment Paper: The parchment paper overhang makes removal from the pan incredibly easy, preventing sticking and ensuring perfectly intact bars.

Serving Suggestions

These Old-Fashioned Amish Rhubarb Oatmeal Crumb Bars are wonderfully versatile.

Rustic Dessert: Enjoy them simply on their own, letting the sweet and tart flavors shine.
Enhanced Indulgence: For an extra treat, serve them warm with a dollop of freshly whipped cream, a scoop of vanilla bean ice cream, or even a drizzle of custard.
Breakfast or Brunch: Their wholesome nature makes them a delightful addition to a breakfast or brunch spread, perhaps alongside fresh fruit or yogurt.
Afternoon Treat: Pair a square with your favorite hot beverage for a comforting afternoon pick-me-up.

If you’re a fan of comforting bar desserts, you might also enjoy our recipe for Cinnamon Roll Bliss Bars, another delightful treat. For more delightful bar recipes to explore, check out these Banana Bread Brownie Bars from Fork Haven™.

Storage & Reheating

These bars store beautifully, allowing you to enjoy them for days.

Room Temperature: Store leftover bars in an airtight container at room temperature for up to 3 days.
Refrigeration: For longer storage, refrigerate in an airtight container for up to a week.
Freezing: These bars freeze beautifully! Once completely cooled, cut them into individual squares and wrap them tightly in plastic wrap, then place them in a freezer-safe bag or container for up to 3 months. Thaw at room temperature or warm gently in the microwave or oven.

FAQ

What type of oats should I use for these Amish Oatmeal Rhubarb Bars?

For the best texture and flavor, use old-fashioned rolled oats. Instant or quick oats will absorb liquids differently and result in a less desirable crumb texture.

Can I use frozen rhubarb instead of fresh?

Yes, you can! If using frozen rhubarb, do not thaw it. Toss the frozen rhubarb directly with the sugar and cornstarch as per the recipe. You might need to bake the bars for a few minutes longer to ensure the rhubarb is tender and the filling is bubbly.

Why is it so important to cool the bars completely before cutting?

Cooling completely, typically 2-3 hours, is crucial for two main reasons: it allows the cornstarch in the rhubarb filling to fully set, giving you a firm, neat filling, and it allows the crumb layers to firm up, ensuring clean, intact squares when cut. If cut warm, the filling will be runny, and the bars will crumble.

How do I know when the Old-Fashioned Amish Rhubarb Oatmeal Crumb Bars are done baking?

The bars are done when the topping is golden brown, and the rhubarb filling is visibly bubbly around the edges and through the crumb topping. You can also gently poke the filling with a knife or toothpick; it should feel tender.

These Old-Fashioned Amish Rhubarb Oatmeal Crumb Bars are a testament to simple, wholesome ingredients creating something truly extraordinary. With their irresistible sweet and tart flavor, comforting texture, and ease of preparation, they are sure to become a cherished recipe in your home. Bake a batch today and savor the taste of tradition!

Amish Oatmeal Rhubarb Bars: Your New Favorite Spring Dessert