Melt 10 tbsp butter over medium heat. Cook butter over medium - low heat stirring frequently while it foams and bubbles. After about 5 minutes, remove from heat and allow to cool.
Whisk sifted flour, salt, baking powder, cocoa and chocolate chips. Set aside.
In an electric mixer, on medium high speed, beat the eggs and sugar for 6-8 minutes until thickened and pale yellow. Beat in the vanilla bean paste and the almond extract.
Gently fold in ½ of the flour mixture. Fold in the butter. Add the remaining flour and fold gently until incorporated. Cover the bowl with plastic and place in the refrigerator for 1 hour.
Preheat the oven to 375°. Using your pastry brush, coat each cavity of the madeleine pan. Dust with flour, tapping off the excess.
Remove the batter from the refrigerator but do NOT stir. Place a heaping tablespoon of batter into each cavity. Do NOT spread the batter - this will happen in the oven. Place the remaining batter in the refrigerator in between baking cookies.
Place the cookies in the oven and lower the temperature to 350°. Bake for 12 minutes or until the cookie springs back to touch.
Remove from the oven and using a fork, lightly loosen the cookie out of the pan. Allow the cookie to cool completely on the rack.
Take the ⅔ cup of semi-sweet chocolate chips and melt in microwave. Using a pastry bag, or plastic bottle, place stripes of chocolate across the cookie.
Store cooled madeleines in airtight containers, layering with waxed paper.