1. Preheat the oven to 350 degrees F. Spray a 9-inch springform pan with nonstick baking spray.
2. In a small bowl, whisk together the flour, baking powder, salt and cinnamon.
3. In the bowl of your electric mixer, beat the butter and sugar together until fluffy and combined, about 5 minutes. Beat in each egg 1 at a time. Beat in the vanilla extract.
4. Beat in half of the dry ingredients, then beat in the milk. Beat in the remaining dry ingredients, scraping the sides and bottom of the bowl as needed, until just combined. Use a spatula to stir in the peaches and the blueberries.
5. Pour the batter into the spring form pan. Make the streusel mixture and sprinkle it all over the top of the batter.
6. Bake the cake for 45 to 50 minutes, or until a tested inserted into the center comes out clean. Let the cake cool for 15 to 20 minutes, then remove the sides of the springform pan. Drizzle on the icing. Let it cool completely before serving.

Crumb topping:

1. To make the crumb topping, whisk together the sugar, cinnamon, salt and melted butter until combined. Whisk for a good minute or two until the sugar begins to dissolve, then use a wooden spoon to stir in the flour. The mixture will be crumb-like and dry. Almost like sludge or sand. This is what you want! Sprinkle the crumb on top of the cake before baking.

Vanilla icing:

1. Whisk together the ingredients until smooth and combined. If the mixture is too thick, whisk in more milk 1 teaspoon at a time. If it’s too thin, add more powdered sugar a few tablespoons at a time.