1 cup whole almonds 
1 cup all-purpose flour
1/2 teaspoon baking powder
1/2 teaspoon salt
8 tablespoons (1 stick) butter, room temperature
1/3 cup sugar
1 egg
1 teaspoon vanilla extract
2 ounces good-quality semisweet chocolate
4 ounces good quality white chocolate

Preheat oven to 350 degrees F. 
 

Place whole almonds on baking sheet. Bake until they're a shade darker and fragrant, about 10 to 15 minutes. Remove from oven and set aside to cool.
 
Lower oven to 325 degrees F.

Place almonds in blender or food processor and pulse to coarse bits; set aside. Whisk together flour, baking powder, and salt to blend; set aside.
 
Beat butter and sugar together with a wooden spoon until smooth. Beat in egg. Gradually beat the flour mixture into the butter mixture. Add the chopped almonds and mix until distributed evenly throughout.
 
Form cookie dough into a log, wrap in plastic and refrigerator for 1 hour.

Slice cookie dough into disks (about 1/4 inch thick) and place on greased cookie sheets. Bake until firm, about 15 minutes. Remove from oven and cool on racks.
 
In a saucepan over lowest heat or in a double boiler, melt white chocolate. Dip the bottom half of cookie into melted white chocolate. Place back on cookie sheet line with parchment paper to harden.

Melt semi-sweet chocolate and with a spoon drizzle over the top of the cookie.
Leave to set (refrigerate if needed to set chocolate)