Preheat oven to 350 degrees. Line half sheet pan with parchment paper. Cream together butter, sugar, in a large bowl. Mix in eggs one at a time, scraping with each addition. Add vanilla; mix. Fold in flour, baking powder, and salt to 80% incorporated. Add mini chocolate chips, gently fold in. Moisten hands with water, divide dough into 2 loaves. (will be sticky)
Place on prepared pan.
Shape into 4 inches wide and 8 inches long loaves (approx).
Bake 30 minutes, or until golden.
Cool on wire rack 15 minutes.
Using a serrated knife cut into 3/4 inch slices.
Place cut side down onto same baking sheet.
Bake additional 20 minutes.
Cool completely.
Place biscotti on parchment paper, drizzle with melted chocolate, and allow chocolate to set.