PREP: Preheat the oven to 350 degrees F. Lightly grease an 8x8-inch metal baking pan with nonstick cooking spray (or for easy cleanup, you can line with parchment and then grease).
DRYINGREDIENTS: In a large bowl, whisk together flour, cinnamon, baking soda, salt, and baking powder. Add in the blueberries and toss to coat. Set aside.
WETINGREDIENTS: In a medium bowl, add the melted and cooled butter, packed brown sugar, maple syrup, and heavy cream. Add in the vanilla extract, almond extract, and Greek yogurt. Zest the outer rind of a lemon (avoid the white pith) to get 1 teaspoon zest. Juice the lemon to get 2 tablespoons juice; add juice and zest to wet ingredients. Whisk until smooth.
COMBINE: Combine wet and dry ingredients. Mix until just combined, being careful not to over mix the batter. The batter is very thick. Spread and then smooth the batter evenly in the prepared pan with a spatula.
STREUSEL: Melt the butter in the microwave and then let stand at room temperature until cooled (don't add hot butter to the streusel -- it will make it greasy). In a separate bowl, whisk together flour, brown sugar, cinnamon, and salt. Add the cooled melted butter and mix until the streusel is evenly combined and forms small clumps. If clumps aren't forming or the streusel is too wet, add more flour, 1 tablespoon at a time. Sprinkle the streusel mixture evenly over the cake batter. Do not press the streusel into the cake.
BAKE: Bake for 37-45 minutes or until the edges begin to pull away from the sides of the pan and a toothpick inserted in the center comes out clean (or with a few moist crumbs attached). (My oven takes 40 minutes.) Cool completely in the pan before adding the glaze.
GLAZE: Whisk all of the icing ingredients together until smooth. Drizzle over entire cooled coffee cake or over individual slices. (See storage note below.)
Notes
Storage: Covered coffee cake will last about 1-2 days at normal room temperature but will stay good for about 1 week in the fridge (in airtight containers). Warm leftover pieces in the microwave and glaze warm. After the first day, the streusel topping does soften and the cake becomes more moist.