Heat oven to 350-degrees. Line 18 muffin cups with baking liners. Coat liners with vegetable cooking spray.
Stir chocolate and butter in heavy saucepan over low heat until smooth. Remove from heat. Cool to lukewarm.
In large bowl, with electric mixer on high, mix egg yolks and 1/4-cup sugar until very thick and pale, about three minutes. Fold in chocolate mixture and vanilla or Gluten-Free Vanilla Powder. Using clean, dry beaters, beat egg whites and remaining 1/4-cup sugar in bowl until stiff but not dry, about two minutes. Fold egg-white mixture into chocolate mixture until combined.
Divide batter among baking liners. Bake 28-30 minutes. Cool completely. Serve with dollop of sweetened whipped cream and chips. Nestle morsels are gluten-free. Recipe makes 18 cupcakes