From A Kitchen in France, by Mimi Thorisson
1 1/2 cups/375 ml whole milk
2 teaspoons crumbled fresh yeast
2 tablespoons granulated sugar
2 cups/240 g all-purpose flour, sifted
3 large eggs, separated
7 tablespoons/100 g unsalted butter, melted
2 tablespoons dark rum
Pinch of fine sea salt
Confectioners’ sugar, for dusting
Warm 2 tablespoons of the milk until lukewarm and mix with the yeast and sugar in a small bowl. Let sit until frothy, 5 minutes.
Put the flour in a large bowl and make a well in the center. Add the yeast mixture to the well, mix it into the flour, and then gradually whisk in the rest of the milk, the egg yolks, melted butter, rum, and salt until you have a smooth batter.
Whisk the egg whites with an electric mixer until stiff, then fold into the batter, using a rubber spatula. Cover and let stand at room temperature for 30 minutes.
Cook the waffles according to your waffle maker’s instructions. Dust with confectioners’ sugar before serving.