1-First Step: Preheat and Prep the Pan Preheat oven to 350°F. Grease a 9×13-inch baking pan with butter or cooking spray. Line with parchment if you like easy removal. This sets up even baking for your moist zucchini coffee cake recipe.

2-Second Step: Make the Streusel Topping In a medium bowl, whisk together ¾ cup flour, ½ cup brown sugar, and 1 teaspoon cinnamon. Cut in ½ cup cold butter using a pastry blender or fingers until crumbly. Set aside. This layer gives the sour cream coffee cake its signature crunch. For vegan diets, use plant-based butter here.

3-Third Step: Shred and Drain the Zucchini Wash two medium zucchini and shred them to yield 2 cups, skin on for extra nutrients. Place shreds in a clean kitchen towel. Squeeze out excess moisture over the sink, removing about ½ cup liquid. Pat dry if needed. Draining prevents sogginess, key for the best sour cream zucchini coffee cake. Salt lightly and wait 10 minutes for pro results.

4-Fourth Step: Mix the Wet Ingredients In a large bowl, beat ½ cup softened butter and 1 cup sugar until light and fluffy, about 2 minutes. Add 2 eggs one at a time, then 1 teaspoon vanilla. Stir in 1 cup sour cream until smooth. For low-calorie versions, light sour cream works well.

5-Fifth Step: Combine Dry Ingredients In another bowl, sift 2 cups flour, 1 teaspoon baking powder, ½ teaspoon baking soda, and ½ teaspoon salt. Gradually add dry mix to wet, alternating with the drained zucchini. Fold gently to avoid overmixing. Batter will be thick.

6-Sixth Step: Assemble and Bake Spread half the batter in the prepared pan. Sprinkle half the streusel. Top with remaining batter, then rest of streusel. Bake 40-45 minutes until a toothpick comes out clean. Cool in pan 15 minutes, then transfer to wire rack.

7-Final Step: Finishing Touches and Serving Dust with powdered sugar if desired. Slice into 12 pieces. Serve warm with coffee. For gluten-free, ensure all flours match. Total time: 60-70 minutes. Store as noted below.