Berry Jam Muffins

These are my new favorite blueberry muffins. You can use any berry in these, I've tried both raspberries and blueberries, but I prefer blueberry. You can also use any berry jam in these as well. They make just a dozen and don't last very long at all.

Berry Jam Muffins
adapted from Joy the Baker who adapted it from the Gourmet Cookbook

6 T unsalted butter
1/3 c milk (whole milk is preferable, but skim works fine)
1 lg egg
1 lg egg yolk
3/4 t vanilla
1 c flour
1/2 c whole wheat flour
3/4 c sugar
1 1/2 t baking powder
3/4 t salt
1/2 - 1 c frozen or fresh blueberries (or whatever berry you may have that you want to use)
3 T strawberry, blueberry, or blackberry jam (or any other berry jam--that's just the ones I've used)

For the topping
1 1/2 T cold unsalted butter, cut into 1/2" cubes
1/4 c flour
1 1/2 T sugar

Melt butter. Whisk in milk, egg, yolk, and vanilla until well combined. Whisk together flour, sugar, baking powder, and salt in a separate medium bowl. Add milk mixture and stir until just combined. Gently but thoroughly fold in berries and jam. Combine all the topping ingredients in a bowl and stir (using your fingers if necessary, which always is for me) until crumbly. Divide batter among 12 muffin cups lined with cupcake papers. Sprinkle topping evenly over batter in muffin tin. Bake in a preheated 375 degrees oven on the rack in the upper third of the oven until the muffins are golden and crisp and a wooden pick inserted in the center comes out clean, 18 - 22 minutes. Cool in pan on rack 15 minutes, then remove muffins from the tin. Serve warm or at room temperature.