A mouth watering muffin.....the top are crumbs....of course mine didn't have enough crumbs..so you can see part of the muffins and I also cut down on the jam/sugar...don't like them too sweet.
Recipe as follows:
(adapted fr: http://www.joythebaker.com/blog/2009/05/raspberry-and-jam-muffins/)

6 Tablespoons unsalted butter

1/3 cup whole milk

1 large egg

1 large egg yolk

3/4 teaspoon vanilla extract

1 1/2 cups all-purpose flour

3/4 cups sugar

1 1/2 teaspoons baking powder

3/4 teaspoon salt

1/2- 1 cup frozen or fresh raspberries (or whatever berry you might have in your freezer or fridge, use as much of the bag or as little as you have left)

3 Tablespoons strawberry jam (or whatever fruit jam you have on hand)

For the topping:

3 Tablespoons cold unsalted butter, cut into 1/2-inch cubes

1/2 cup all-purpose flour

3 1/2 tablespoons sugar

Put a rack in the upper third of oven and preheat to 375 degrees F. Generously butter muffin cups or line with cupcake papers.

Melt butter in a small saucepan over moderately low heat; remove from heat. Whisk in milk, egg, yolk and vanilla until well combined.

Whisk together flour, sugar, baking powder, and salt in a medium bowl. Add milk mixture and stir until just combined. Gently but thoroughly fold in the berries and the jam.

Divide batter among muffin cups and spread evenly.

For the topping:

Combine all the topping ingredients in a bowl and rub together with your fingertips until crumbly. Sprinkle evenly over batter in cups.

Bake until golden and crisp and a wooden pick inserted into center of a muffin comes out clean, 18-22 minutes. Cool in pan on a rack for 15 minutes, then run a knife around edges of muffin tops and carefully remove from cups. Serve warm or at room temperature.

A recipe to keep and to repeat.