- 20 to 25 spears asparagus
- 3 T unsalted butter
- 3/4 C whole milk (or half whole milk and half 1/2 and 1/2)
- 3 large egg yolks, lightly beaten
- 1 t flour (optional)
- 8 ounces Fontina cheese, cut into 1/4-inch cubes
Bend the thick end of each asparagus spear until it snaps and discard the fibrous end piece. Steam the asparagus spears in a vegetable steamer until they are just tender and offer only a little resistance when pierced with the tines of a fork. Remove to a warm platter and keep warm.
Place the butter in the top of a double boiler. Make sure the water in the bottom does not touch the top pan. Bring the water in the double boiler to a boil over medium high heat. While the butter is melting, beat together the milk, eggs, optional flour, and add the cheese. Slowly whisk the egg and milk mixture into the pan with the butter, continuing to whisk until it has thickened and a sauce has formed, about 10 minutes.
To serve, drizzle the sauce over the asparagus.