Preheat oven to 350 degrees F. Spray a 9x5 inch loaf pan with cooking spray.

Prepare the crumb topping. Combine ¼ cup brown sugar with 6 tablespoon all-purpose flour, 1 teaspoon cinnamon, and 3 tablespoon butter. Blend with a pastry cutter or a fork until the butter is well incorporated. The crumb topping should have the texture of coarse sand.

Make the pancake bread. Cream together softened butter with brown sugar until softened and whipped, about 2 minutes. Add eggs one at a time, mixing well before adding the next egg.

Combine maple syrup with buttermilk, vanilla, and Greek yogurt in a medium bowl. In another bowl, mix together flour with baking soda, baking powder, and salt.

Add a third of the dry ingredients to the creamed mixture followed by half of the wet ingredients. Stir until just combined, then add another third of the dry ingredients, followed by the remaining wet ingredients. Finish with the remaining third of the dry ingredients, stirring until just combined. Pour batter into prepared baking loaf pan. Sprinkle crumb topping on top in an even layer.

Bake in the oven for 45 minutes – 1 hour or until a toothpick inserted in the center comes out clean. Cool on a wire rack for 15 minutes. Serve pancake bread warm.