1/2 cup unsalted butter at room temperature
3 oz. cream cheese at room temperature
1 cup all-purpose flour
If using a mixer, cream butter and cream cheese together until smooth. Add the flour and mix on low speed until a smooth dough forms. You can also do the same thing by hand.
Roll dough into half-inch balls and place in mini-muffin pan. Using your fingers, shape the balls to evenly cover the indentation in the tart pan. Another easier alternative is to use a tart plunger, available at most cooking stores. Just dust the wooden plunger with flour and press the dough ball into the tart pan.
If you plan to fill them after baking, bake until golden brown at 375 degrees for about 8 - 10 minutes. Cool on rack.
If you are baking with a filling (quiche, pecan pie, etc), bake until filling is set at 375 degrees.