Chocolate Filled Almond Macaroons

7 ounces almond paste
1 cup granulated sugar
2 large egg whites
40 whole almonds (about)

Ganache:
1/4 cup whipping cream
2 tablespoons (1/4 stick) unsalted butter
1/2 teaspoon grated orange peel
6 ounces bittersweet (not unsweetened) or
    semisweet chocolate, finely chopped

Heat oven to 375 degrees F. Generously butter heavy large nonstick cookie sheets.

Blend almond paste, sugar and egg whites in processor until smooth. Drop dough by slightly rounded teaspoonsful onto prepared sheets, spacing evenly. Press 1 almond onto each mound. Bake until cookies are golden brown, about 10 minutes. Let cookies rest on sheets until just cool to touch, about 5 minutes. Using spatula, transfer cookies to rack and cool completely. (Can be prepared 1 day ahead. Store cookies in airtight container at room temperature.)

Bring cream, butter and orange peel to simmer in heavy small saucepan. Reduce heat to low. Add chocolate and stir until mixture is smooth. Remove from heat and let ganache stand until thick but spreadable, about 20 minutes.

Spread some ganache over flat side of 1 cookie. Sandwich with flat side of another cookie. Repeat with remaining cookies and ganache. (Can be prepared 2 days ahead. Cover and refrigerate in airtight container. Bring cookies to room temperature before serving.)