Step 1

Preheat your oven to 350 degrees F.

Step 3

Melt 1/3 cup of the butter in a 9-inch microwavable square cake pan in the microwave.

Step 5

Sprinkle the brown sugar over the melted butter, and then add the rhubarb to the pan.

Step 7

In a stand mixer, using a paddle attachment, cream the remaining 1/3 cup softened butter and granulated sugar together until smooth.

Step 9

In a bowl, mix the flour, baking powder, and salt together. While continuing to mix on low, slowly add the dry ingredients to the creamed butter-sugar mixture.

Step 11

Then add the milk, vanilla, and egg. Continue to mix for 2 minutes on medium speed until well combined.

Step 13

Spread the batter over the rhubarb in the pan.

Step 15

Bake for about 40 minutes, or until the batter is golden brown and fully cooked, don’t overbake, though, as you will lose your pudding layer. You want the cake just done to spring back. If using frozen rhubarb, then bake for an additional 10 minutes.

Step 17

Serve warm with a scoop of vanilla ice cream. Enjoy!