In a medium bowl, whisk the 2 1/2 cups of flour, baking powder, and kosher salt until combined. Set aside.
2 1/2 cups All-purpose flour, 2 1/2 tsp Baking powder, 1 tsp Kosher salt
In a large bowl, whisk in the eggs and sugar until they’re thick, about 1 minute. Slowly whisk in the melted and cooled butter until combined. Whisk in the buttermilk, peach preserves, vanilla, and almond extract until smooth and combined.
2 large Eggs, 3/4 cup Granulated sugar, 1/2 cup Unsalted butter, 1 cup Buttermilk, 1/3 cup Peach preserves, 1 tsp Vanilla extract, 1/4 tsp Almond extract
Toss the peaches with 2 teaspoons of flour. Fold the dry ingredients into the wet ingredients just until almost combined. Fold in the peaches. Do not overmix.
1 1/2 cups diced Fresh peaches, 2 tsp All-purpose flour
Let the batter rest for 15 minutes while you preheat the oven to 425ºF and line a muffin pan with paper liners.
Divide the batter equally into the muffin cups. Sprinkle the top of each muffin with about 2 tablespoons of streusel. Bake for 5 minutes at 425ºF, then reduce the oven temperature to 350ºF and bake for an additional 15-20 minutes or until a toothpick inserted into the center of a muffin comes out clean; do not overbake. Let the muffins cool in the pan for about 5 minutes, and transfer to a wire rack to cool completely.