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.
I was looking for the same thing and found this link:
http://www.bakedeco.com/detail.asp?id=14511&trng=fgle
I was wondering where I can order the pannetone muffin liners you used for this recipe. I can only seem to find them in quantities of 6 or 24. You mentioned that you could buy 100 for about 15.00. Please let me know. I think they are beautiful and would like to make the recipe using these baking cups. Thanks