2 tablespoons unsalted butter, plus more for the pan
1 large egg
1 large egg yolk
1 cup half-and-half
3/4 cup all-purpose flour
Salt and freshly ground pepper
1/2 cup strawberry or peach jam
1/2 cup Nutella
Preheat the oven to 225°. In an 8-inch nonstick skillet, brown the 2 tablespoons of butter over moderately high heat, about 4 minutes. Transfer to a bowl and let cool.
In a medium bowl, whisk the egg and egg yolk with the half-and-half. Whisk in the flour and browned butter. Season the batter with salt and pepper.
Set the skillet over high heat. When it is hot, add a scant 1/4 cup of batter, swirling to coat the bottom of the pan. Cook until the crêpe is browned around the edges and the top is set, about 45 seconds. Flip the crêpe and cook until the underside is lightly browned, about 30 seconds longer. Transfer the crêpe to a plate. Repeat with the remaining batter, buttering the pan as needed. You should have about 8 crêpes.
Spread each crêpe with 1 tablespoon of the jam and fold into quarters. Transfer the crêpes to a small baking dish, overlapping slightly. Bake for 10 minutes, until the crêpes are just heated through.
Meanwhile, in a small microwave-safe bowl, heat the Nutella in a microwave oven on high power in 20-second bursts just until runny. Drizzle the Nutella over the warm crêpes and serve.
The crêpes can be prepared through Step 3, covered with plastic wrap and refrigerated overnight.