1. Pulse first 3 ingredients in a food processor until blended. Add butter, and pulse until mixture resembles coarse meal.
2. Combine egg yolk and cream in a small bowl. Add mixture to food processor, and process until dough starts to come together.
3. Remove dough from processor, knead several times, and pat into a flattened disc. Wrap in plastic, and chill until ready to use. (Dough may be frozen up to 1 month and thawed overnight in refrigerator.)
4. Roll out chilled dough to 1/8- to 1/4-inch thickness, and fit into a 10-inch tart pan. Chill 20 minutes.
5. Preheat oven to 375°. Line chilled tart shell with parchment paper, and weight with rice, dry beans, or pie weights. Bake 20 to 25 minutes or until crust just begins to turn golden brown. Remove parchment and weights, and bake 7 minutes more or until bottom of shell turns light golden brown. If pastry bubbles up, prick gently with a fork. Remove from oven, and let cool completely.