Ingredients

Equipment Needed

• •Heatproof bowl for melting chocolate
• •Medium pot for the bain-marie
• •Large mixing bowls (2, completely dry)
• •Whisk or electric hand mixer
• •Flexible spatula
• •6 small serving cups, ramekins, or vintage glasses (150ml capacity)

Instructions

1. 1

   Melt the chocolate

   Set a heatproof bowl over a pot of barely simmering water. The bowl should not touch the water. Add the chopped chocolate and butter. Let them melt slowly, stirring occasionally with a spatula until smooth and glossy. Remove from heat and stir in the coffee and aguardente if using. Let it cool until warm but not hot. You should be able to touch the bottom of the bowl comfortably.

   Patience with the chocolate. If it seizes from too much heat or a drop of water, you'll have to start over. Low heat, dry equipment, no rushing.
2. 2

   Beat the yolks

   In a large bowl, whisk the egg yolks with half the sugar until thick, pale, and doubled in volume. This takes 3 to 4 minutes by hand, longer if your arm is tired. The mixture should fall in thick ribbons when you lift the whisk. This is where the richness builds. Bate, bate, bate. The yolks need air.

3. 3

   Combine yolks and chocolate

   Pour the warm (not hot) chocolate mixture into the yolks in a slow stream, folding gently as you go. Work in one direction, from the bottom up, rotating the bowl. The mixture should be uniform and glossy, dark as good earth. Set aside.

4. 4

   Whip the whites

   In a clean, dry bowl, beat the egg whites with the salt until they hold soft peaks. Add the remaining sugar gradually, beating until the whites are glossy and hold firm peaks but aren't dry. They should look like satin, not cotton.

   Any trace of yolk in your whites and they won't whip properly. Separate eggs one at a time over a small bowl first, then transfer whites to your mixing bowl. One broken yolk shouldn't ruin the whole batch.
5. 5

   Fold everything together

   Add one third of the whites to the chocolate mixture and fold vigorously to lighten. This first addition can be rough. Then add the remaining whites in two additions, folding gently each time. Use a spatula, cut through the center, sweep under and up, rotate the bowl. Stop the moment you no longer see white streaks. Overmixing is the enemy. Every extra fold costs you air.

6. 6

   Chill and serve

   Divide the mousse among six small cups, ramekins, or vintage glasses. Cover loosely and refrigerate for at least 4 hours, preferably overnight. The mousse needs time to set and the flavors to deepen. Serve cold with a spoonful of whipped cream and chocolate shavings if you like. Or serve it bare, the way Avó Leonor did, letting the chocolate speak for itself.

Chef Tips

• •Room temperature eggs are not optional. Cold eggs don't whip properly and cold yolks seize when they hit warm chocolate. Take them out of the fridge an hour before you start.
• •Use the best chocolate you can afford. You're eating it almost straight, with nothing to hide behind. Portuguese chocolate from brands like Regina or Imperial works beautifully, but any 70% cacao with good flavor will do.
• •The coffee doesn't make the mousse taste like coffee. It deepens the chocolate, makes it more itself. A Portuguese tradition that works. Trust it.
• •This mousse is denser than what you might expect. That's correct. We use more yolks than the French. More yolks means more richness, more silk, more history. Don't let anyone tell you it's wrong.

Advance Preparation

• •The mousse must chill for at least 4 hours, but overnight is better. Plan accordingly.
• •It keeps beautifully in the refrigerator for up to 3 days, covered. The flavor deepens as it sits.
• •Bring the serving cups out 10 minutes before serving. Slightly less cold lets the chocolate flavor bloom.

Frequently Asked Questions

Nutrition Information

1 serving (about 115g)