Warm, buttery, Cinnamon Walnut Cake uses a tender sour cream batter and a cinnamon-walnut streusel, for a bakery-style cake at home. Perfect for breakfast or brunch!
Preheat oven to 350 F. Lightly grease a 9X9 inch pan or line with parchment paper.
In medium sized mixing bowl whisk together ½ cup milk , ½ cup sour cream or plain greek yogurt, 1 egg, ¼ cup vegetable oil, 1 teaspoon vanilla, ¾ cup granulated white sugar, and ½ teaspoon salt. Mix well.
Add1½ cups all-purpose flour and 2 teaspoons baking powder, mix together until fully combined and no flour pockets are left but do not overmix.
Place batter in prepared 9X9 inch pan.
For the oat crumble topping:
In a small bowl combine 1 cup rolled oats,½ cup brown sugar,2 Tablespoons flour,2 teaspoons cinnamon, 4 Tablespoons melted butter , ½ cup chopped walnuts and mix well, then spread over cake batter evenly to cover.
Bake at 350 F for 40-45 minutes (glass or heavy ceramic pans may take a few minutes longer), until inserted toothpick comes out clean.
Notes
Can be doubled in a 9x13 inch pan. Simply increase baking time to 50-60 minutes or until an inserted toothpick comes out clean. To make overnight:
Make recipe as directed.
Place in refrigerator overnight, and when ready to bake increase baking time by 5-10 minutes. Make sure to never place a glass pan in a very hot oven or it could shatter. Put it in as the oven is preheating.
Insert toothpick every 5 minutes after 40 minutes to check doneness.
Recipe adapted from an old edition of Better Homes and Gardens cookbook.