We think this spin on classic hollandaise sauce—made with crème fraîche rather than cooked over a double boiler—is brilliant. When drizzled over the warm mushrooms, it melts just enough that you'll wonder if it's the real thing.
4 large eggs
3 tablespoons melted butter, divided
1 tablespoon extra-virgin olive oil
8 ounces cremini mushrooms, stems removed and quartered
4 ounces chanterelle mushrooms, cut into 1-in. pieces
4 ounces oyster mushrooms, cut into 1-in. pieces
1/2 teaspoon salt
1/2 cup crème fraîche
1 1/2 teaspoons Dijon mustard
1 teaspoon lemon juice
2 teaspoons lemon zest
About 6 cups watercress with tough stems removed
How to Make It
Bring a medium saucepan of water to a boil. Using a slotted spoon, gently submerge eggs into water. Simmer 5 minutes, then carefully immerse in cool water.
Heat 1 tbsp. butter with the oil in a 12-in. frying pan over medium-high heat. Add mushrooms and sauté until browned, about 8 minutes, then season with salt.
Whisk together crème fraîche, mustard, and lemon juice and zest in a small bowl. Gradually whisk in remaining 2 tbsp. butter to make hollandaise sauce.
Divide watercress among plates. Top with warm mushrooms, then drizzle with hollandaise. Crack an end of each egg and peel a quarter of shell. Using a spoon, carefully loosen eggs from their shells and scoop onto salads. Add a few turns of pepper on top.