1. Remove wrappers from chocolates; place in freezer while preparing and baking cookies.
2. Beat butter, granulated sugar, water and vanilla in large bowl on medium speed of mixer until well blended. Add eggs; beat well. Stir together flour, cocoa, salt and baking soda. Gradually add to sugar mixture, beating on low speed until blended. Cover; refrigerate dough about two hours or until firm enough to handle.
3. Heat oven to 350°F. Line 48 small muffin cups (1-3/4 inches in diameter) with paper or foil baking cups or lightly spray with nonstick cooking spray. Shape dough into 1-inch balls; place in prepared muffin cups.
4. Bake 11 to 13 minutes or until cookie surface is set. Cookies will appear soft and moist. Do not overbake. Cool about 5 minutes on wire rack. Dust cookie tops with powdered sugar. Press frozen chocolate piece into surface of each cookie. Cool completely in pan on wire rack. Makes 48 brownie bites.