Combine blueberries and ¼ cup water in a small saucepan and simmer until blueberries have broken down and thickened. Blend blueberries till smooth.

Spread melted chocolate on a parchment-lined sheet tray and refrigerate.

Place egg yolks in a large bowl.

Combine milk, sugar and vanilla in a stainless-steel pot. Bring to a boil and use to temper egg yolks by slowly adding 2 cups of hot milk mixture to the yolks whisking constantly.

Turn off heat. Add tempered yolks back into remaining milk and stir with a rubber spatula.

Chill mixture in an ice bath. Once ice cream is cold, add blueberry puree. Churn in an ice cream machine and, after ice cream is frozen, fold in chocolate shards.