Step 1

To prepare rhubarb for this gluten-free buttermilk cake, wash the stalks under cold water, and dry them. Remove the ends and leaves.

Step 2

Cut the stalks into small pieces, around ½ inch to 1 inch in length. If you like you may also cut some smaller pieces and add them to the actual cake batter. I only use rhubarb to top the cake. Make sure though to macerate the smaller pieces in a separate bowl.

Step 3

Add the sliced rhubarb to a small bowl and toss them with some granulated sugar and lemon juice. You can even add some lemon zest if you like. Let the mixture sit, stirring occasionally, until the sugar has dissolved and the rhubarb has released some of its juices.

Step 4

Let the mixture sit while you prepare the gluten free cake batter. Drain off any excess liquid though before adding the rhubarb to your recipe and reserve it for later use if you like. It does make a delicious drizzle for the finished Rhubarb Cake

Step 5

Preheat the oven to 350F. Grease a 9" springform pan with nonstick spray and line the bottom with parchment paper.

Step 6

Mix butter, powdered sugar, vanilla extract, and almond extract (if using) in a mixing bowl or stand mixer. Beat for 3 minutes until smooth and light in color, stopping to scrape the sides of the bowl.

Step 7

Add the room temperature eggs one at a time, waiting 30 seconds between each addition. The batter will look curdled.

Step 8

In a separate bowl, combine the gluten-free multi-purpose flour, almond flour, baking powder, and salt. Add the flour mixture to the wet ingredients and mix until everything is combined. The batter will be stiff.

Step 9

Pour in the room-temperature buttermilk and mix until fully incorporated. Scrape the bowl to ensure everything is well combined.

Step 10

Spread the gluten-free rhubarb cake batter evenly in the prepared 9" spring form.

Step 11

Retrieve the bowl with the sliced rhubarb. Drain the syrup and arrange the pieces of rhubarb on top of the cake to your liking.

Step 12

Sprinkle with coarse sugar and sliced almonds.

Step 13

Place the rhubarb coffee cake in the preheated oven and bake at 350F for 45-50 minutes. The top of the cake will be golden brown and a cake tester insert in the center of the cake comes out clean.

Step 14

Cool the cake in the pan for 10 minutes before removing the springform ring. Serve warm with powdered sugar, or let cool completely on a wire rack.