Melt the chopped chocolate and butter together in the microwave in 1 minute increments or over a double boiler, careful not to burn the chocolate. When it’s mostly melted the heat of the rest will melt what’s leftover, stir until smooth and let cool.

In a stand mixer or with a bowl and a hand mixer, beat the sugar and eggs together until very light and fluffy, for about 4 minutes - the mix should fall back into the bowl in ribbons.

Slowly pour in the cooled chocolate mixture while beating.

Add flour and baking powder and whisk to just combine. If you’re adding chocolate chips, add them now.

Let dough sit, uncovered for about 15 minutes at room temperature.

Preheat the oven to 350 F and line two cookie sheets with parchment paper. You MUST use parchment or these cookies will stick to the pan.

Portion cookies into 1.5 tablespoons dough, leaving room for them to spread. If topping with sea salt, sprinkle it on now.

Bake until the cookies have puffed up, spread and cracked - they should look set all over (not wet), about 9 minutes.

Wait for cookies to cool before moving (they stick more to the parchment when hot). Store in an airtight container.