Double Crumb Rhubarb Coffee Cake

Double crumb rhubarb coffee cake is my go-to bake when rhubarb pops up at the market and the house is begging for something comforting. The buttery cake comes out soft with a sweet tart kick from rhubarb and extra crunch thanks to a double layer of cinnamon crumb. This recipe is just the right balance of homey and impressive plus it brings back memories of spring Sundays with the windows cracked open.

I first made this cake after my neighbor left a bag of homegrown rhubarb at my door. Now it is a staple for brunches and summer potlucks and even the kids insist on an extra crumb layer every time.

Ingredients

• Butter: For structure and rich flavor. Use fresh unsalted butter for best taste
• Sugar: Gives the cake its sweet crumb without overpowering the rhubarb
• Eggs: Add lightness and help bind the cake. Let them come to room temperature for even mixing
• Plain Greek yogurt or sour cream: Adds moisture and subtle tang so the cake stays soft
• Vanilla: For warmth and aroma. Real vanilla extract works best
• All-purpose flour: Creates tenderness and structure in both the cake and crumb
• Baking soda: Reacts with the yogurt to lift the cake. Check your box is fresh for a good rise
• Rhubarb: Brings that classic tart bite. Look for crisp bright stalks and chop finely for even baking
• Brown sugar: In the crumb topping gives deep caramel notes and a soft crunch layer
• Cinnamon: For cozy fragrance. Fresh cinnamon adds a noticeable difference
• Cold butter: In the crumb helps the topping stay chunky and crisp as it bakes

Step-by-Step Instructions

Prepare the Pan:

Grease a nine by thirteen inch pan thoroughly with butter or nonstick spray to prevent sticking. Set aside within easy reach

Make the Cake Batter:

In a large bowl cream softened butter and sugar together until pale and fluffy. Use a hand mixer on medium speed for three to four minutes. Beat in eggs one at a time mixing until fully incorporated with each addition. Stir in vanilla extract followed by Greek yogurt. Scrape down bowl as needed so the mixture is totally smooth

Combine Dry Ingredients:

In a separate medium bowl whisk flour and baking soda together to make sure they are evenly distributed. This prevents pockets of baking soda in the finished cake

Mix Batter:

Add dry ingredients to the wet ingredients all at once. Gently fold together with a spatula or spoon. Stop as soon as no streaks of flour remain. Overmixing leads to a tough cake. Fold in two thirds of the finely diced rhubarb making sure pieces are coated and dispersed

Make the Crumb Topping:

In a small bowl stir together brown sugar flour and cinnamon. Cut cold butter into tiny cubes and using a pastry blender or two knives cut it into the mixture until it forms moist clumps about pea sized

Layer the Cake and Crumbs:

Spread half of the cake batter into the prepared pan using an offset spatula to reach all the corners. Sprinkle with half the crumb topping followed by the remaining rhubarb pieces. Carefully dot the rest of the batter across the top and spread gently to cover most of the rhubarb. Sprinkle over all the remaining crumb topping so it covers the surface

Bake the Cake:

Place the pan in the center of a preheated three hundred fifty degree oven. Bake for thirty to thirty two minutes or until a toothpick inserted near the center comes out with just a few moist crumbs. The top should look golden with the crumb set firm

Cool and Serve:

Let the cake cool in the pan for at least fifteen minutes so the crumb sets. Serve warm or at room temperature. Cut into squares for sharing

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My absolute favorite part is the double crumb topping. My grandmother always insisted on an extra layer of crumb for “good luck” and now it is non negotiable when I bake this at home. There is nothing like that sweet cinnamon crunch melting into a tart pocket of rhubarb to take you back to childhood.

Storage tips

Once cooled cut the cake into squares and store in an airtight container at room temperature for up to three days. For longer storage wrap each piece tightly in plastic and freeze for up to three months. To reheat simply pop a square in the microwave for ten seconds and it will taste just like fresh from the oven.

Ingredient substitutions

You can swap plain Greek yogurt for sour cream if needed this will keep the cake moist and tender. If fresh rhubarb is out of season use frozen rhubarb but thaw and drain it well before adding to the batter. For those avoiding nuts this recipe is already nut free but a handful of chopped pecans can be sprinkled into the crumb for extra crunch.

Serving suggestions

This cake is perfect with hot coffee or tea for breakfast but also shines as an afternoon snack or light dessert. Top warm slices with a dollop of whipped cream or serve with a scoop of vanilla ice cream for a decadent treat on summer evenings. For a brunch spread slice into small cubes and serve in cupcake papers.

Cultural or historical context

Rhubarb coffee cake like this harks back to Midwest farm kitchens where rhubarb was one of the first spring crops and home bakers would whip up cakes and jams to make the most of its brief season. The double crumb style is a nod to old German and Scandinavian streuselkuchen which layered crumb both inside and out for extra sweetness and texture.

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When I bake this for friends someone always asks for the recipe before a second slice. There is just something about those layers of sweet crumb and tart fruit that makes a kitchen feel like home as soon as it comes out of the oven.

Frequently Asked Questions

→ Can I use frozen rhubarb?

Yes, frozen rhubarb works well. Thaw and drain excess moisture before using for best results.

→ What's the best way to store leftovers?

Store in an airtight container at room temperature for 2 days, or refrigerate for up to 5 days.

→ Can I substitute sour cream for Greek yogurt?

Absolutely. Both provide moisture and tang, so use whichever you prefer or have on hand.

→ How do I achieve a tender crumb?

Be careful not to overmix the batter. Gently fold the dry and wet ingredients together just until combined.

→ Is it possible to make this cake ahead?

Yes, it keeps well. Bake a day in advance and store covered; flavors deepen and crumbs stay crisp.