Preheat oven to 400°F. Prepare muffin tin by spraying with baking spray or lining with cupcake liners.
In a large bowl, whisking together the flour, sugar, baking powder and salt.
2 cups (282g) all-purpose flour, 1 cup (200g) granulated sugar, 2 teaspoons baking powder, 1/2 teaspoon salt
In a separate bowl, whisk together the eggs, melted butter, oil, buttermilk, and vanilla.
2 large eggs, 1 cup buttermilk, 1/4 cup salted butter, 1/4 cup vegetable oil, 1 teaspoon pure vanilla extract
Add the liquids to the flour mixture, stirring with a spoon just until no streaks of flour remain.
Gently fold in raspberries (toss frozen berries in 2 teaspoons of flour to keep them from “bleeding” into the muffin batter).
1 1/2 cups raspberries
Divide muffin batter evenly into the prepared muffin pan. Cups will be very full.
In a small bowl, make the streusel by stirring together the flour, sugar, salt, and ginger. Cut the butter into flour mixture using a pastry cutter until it resembles coarse crumbs. Pick up the streusel mixture by handfuls and give it a squeeze to form small clumps. Spoon a heaping tablespoon of streusel over each muffin.
2/3 cup (94g) all-purpose flour, 1/3 cup (66g) granulated sugar, 1/4 teaspoon ground ginger, 1/8 teaspoon salt, 4 Tablespoons cold salted butter
Bake for 18-22 minutes, or until a toothpick inserted into the center of a muffin comes out with only a few moist crumbs attached. Cool completely then store in an airtight container.