Ingredients
1 1/2 cups all-purpose flour
1/2 cup packed dark-brown sugar
1/2 teaspoon salt
3/4 teaspoon ground cinnamon
1/2 cup (1 stick) unsalted butter, melted and cooled
2 cups all-purpose flour
1 teaspoon baking powder
1 teaspoon baking soda
1/2 teaspoon coarse salt
12 tablespoons unsalted butter, room temperature
1 cup granulated sugar
2 large eggs
2 large egg yolks
1 teaspoon pure vanilla extract
2/3 cup creme fraiche
Heaping 1/4 cup jam
Preparation
Preheat oven to 325 degrees. Place twelve 2 3/4-by-2-inch panettone papers on a rimmed baking sheet; set aside.
Make the topping: In a large bowl, whisk together flour, brown sugar, salt, and cinnamon. Add melted butter and, using a rubber spatula, toss until large crumbs form. Set aside.
Make the muffins: In a medium bowl, whisk together flour, baking powder, baking soda, and salt; set aside. In the bowl of an electric mixer fitted with the paddle attachment, cream together butter and sugar until light and fluffy, 2 to 3 minutes. Add eggs, egg yolks, and vanilla. Add flour mixture alternating with creme fraiche and mix until well combined.
Divide batter evenly between muffin cups. Add 1 heaping teaspoon jam to each muffin cup and evenly divide crumb topping among muffin cups. Transfer to oven and bake until golden brown and a cake tester inserted into the center comes out clean, 20 to 25 minutes. Transfer muffins to a wire rack to cool.
