Spray a 9 by 9-inch glass baking dish with nonstick spray and set aside.
In a medium mixing bowl whisk together the flour, baking powder, salt and ginger. Set aside.
In the bowl of a stand mixer, with the paddle attachment, beat together the yogurt and sugar on medium speed until light and fluffy, approximately 1 minute.
Add the egg and beat until thoroughly combined, approximately 30 seconds.
Add ⅓ of the flour mixture and beat on low speed just until incorporated and then add ⅓ of the milk and beat until incorporated. Repeat, alternating flour and milk until everything has combined.
Gently stir in the blueberries and pour the mixture into the prepared baking dish.
for the topping
In a small bowl combine the sugar, flour and ginger.
Add the yogurt and work into the dry ingredients using a fork to combine.
Continue until the mixture has a crumb-like texture.
Place and gently press peaches into top of cake while sprinkling the streusel on top of the cake.
Bake on the middle rack of the oven for 35 minutes or until golden in color.
Cool for at least 10 minutes before serving.
As with any recipe, make this one your own. Don't care for ginger? How about a dash of nutmeg, a sprinkle of cinnamon, or all of the above? An alternative to folding the berries into the batter is to pour half the batter into baking pan, evenly distribute berries on that layer, then pouring remaining cake batter over berries.