1teaspoonxanthan gumomit if your blend already contains it
6tablespoons(84g)unsalted butterat room temperature
1cup(256g)sour creamat room temperature
2tablespoons(1fluid ounce)milkat room temperature
1teaspoonpure vanilla extract
2(100g (weighed out of shell))eggsat room temperature
Preheat your oven to 350°F. Line an 8-inch square baking pan with parchment paper and set it aside.
For the crumble topping
The topping must be prepared first, so it can chill.
In a medium-size bowl, place all the ingredients in the order listed, mixing to combine after each addition.
Cover the bowl that holds the raw topping. Place the bowl in the refrigerator to chill until firm.
For the cake batter
In a medium-size bowl, place the flour, xanthan gum, cornstarch, baking powder, baking soda, salt, and optional cinnamon, and whisk to combine well. Set the bowl aside.
In a large bowl with a handheld mixer or the bowl of a stand mixer fitted with the paddle attachment, place the butter, sour cream, granulated sugar, milk, and vanilla, and beat well on medium speed until very smooth. Add the eggs, and beat until just combined.
Add the dry ingredients to the bowl of wet ingredients and mix by hand until just combined. The batter will be very thick, since our liquid is mainly sour cream.
Assemble and bake the cake
Scrape the batter into the prepared pan and smooth into an even layer with a wet spatula. Press the spatula down in the corners to eliminate any air pockets.
Remove the chilled crumble topping from the refrigerator. Uncover the topping, and use the tines of a fork to break up the mixture into irregular pieces.
Scatter the crumble pieces evenly on top of the cake batter. Press down gently to help the topping adhere to the batter.
Place the cake pan in the center of the preheated oven. Bake for about 40 minutes, until the center does not jiggle in the center when the pan is shaken from side to side gently.
A cake tester inserted into the center should come out mostly clean. Do not overbake or the bottom will burn.
Remove the pan from the oven and allow the cake to cool to warm room temperature in the pan. Slice into squares and serve.
Originally published on the blog in 2012. Recipe tweaked slightly (less sugar, less butter in cake batter), photos, video and text all new in 2021.
Easy Gluten Free Coffee Cake Recipe | Extra-moist with sour cream from Nicole Hunn at Gluten Free on a Shoestring. Find recipe online at https://glutenfreeonashoestring.com/gluten-free-coffee-cake/