Preheat oven to 300°.
Beat egg whites, cream of tartar, and salt at high speed of a mixer until soft peaks form. Add sugar, 1 tablespoon at a time, beating until stiff peaks form. Sift cocoa over egg white mixture; fold in. Fold in minichips.
Cover a baking sheet with parchment paper; secure to baking sheet with masking tape. Drop batter by level tablespoonfuls onto prepared baking sheet. Bake at 300° for 40 minutes or until crisp. Cool on pan on a wire rack. Repeat procedure with remaining batter, reusing parchment paper. Store in an airtight container.
These cookies are lighter than traditional chocolate-chip cookies because they are made primarily with egg whites and not grains. They are also lower in fat and calories.