Go Back

Rhubarb Breakfast Cake

Rhubarb breakfast cake with a tender crumb, rhubarb pockets, and a cinnamon crumb topping. Baked in a 9x9 pan until golden, then cooled briefly so it slices cleanly and tastes warm with coffee.
Print Recipe Pin Recipe
Prep Time 15 minutes
Cook Time 40 minutes
cooling 15 minutes
Total Time 1 hour 10 minutes
Servings: 9 servings
Course: Breakfast
Cuisine: American
Calories: 330
Ingredients Equipment Method Notes

Ingredients
  

For cake
  • 1.5 cup all-purpose flour
  • 1 cup sugar
  • 2 tsp baking powder
  • 0.5 tsp salt
  • 0.5 cup butter, melted
  • 1 egg
  • 0.75 cup milk
  • 1 tsp vanilla extract
  • 2 cup fresh rhubarb, diced
For topping
  • 0.333 cup brown sugar
  • 0.25 cup all-purpose flour
  • 2 tbsp butter, cold
  • 0.5 tsp cinnamon

Equipment

  • 1 sheet pan

Method
 

Prepare and mix the cake
  1. Preheat your oven to 350°F and grease a 9x9-inch baking pan so the batter releases cleanly.
  2. Whisk together all-purpose flour, sugar, baking powder, and salt in a mixing bowl until evenly combined and lighter in color.
  3. In a separate bowl, mix melted butter, egg, milk, and vanilla extract until smooth.
  4. Pour the wet mixture into the dry ingredients and stir until just combined, keeping the batter thick and avoiding overmixing.
  5. Fold in the diced fresh rhubarb so the pieces are evenly distributed through the batter.
Add topping and bake
  1. Spread the batter into the prepared 9x9-inch pan in an even layer.
  2. For the topping, mix brown sugar, all-purpose flour, and cinnamon, then cut in cold butter until crumbly.
  3. Sprinkle the cinnamon crumble topping evenly over the batter.
  4. Bake at 350°F for 35-40 minutes until the top is golden and a toothpick inserted in the center comes out clean.
Cool and serve
  1. Cool the cake for 15 minutes before serving warm so the crumb sets for clean squares.

Notes

Pro tip: dice the rhubarb small and pat off excess moisture so the cake bakes through without pooling. Store covered in the refrigerator for up to 4 days; rewarm individual squares in the microwave for 15-25 seconds. Freezing is yes—wrap tightly and freeze up to 2 months, then thaw overnight in the fridge. For a lighter option, replace half the sugar with an equal amount of light brown sugar and keep the rest the same for the best crumble texture.