Coquilles Saint Jacques

Melt butter in a large skillet over medium heat; saute shallots in hot butter until translucent, 5-8 minutes. Stir in the mushrooms and S&P. Turn heat to medium-high and cook, stirring often, for 10 minutes.

Pour wine over mushroom mixture, dissolving any brown bits of food on bottom of skillet into wine;bring to a simmer. Gently place scallops into wine and poach in mixture about 2 minutes each side. Transfer scallops to a bowl. Strain mushroom mixture into another bowl, reserving mushrooms and cooking liquid separately. Return strained liquid to skillet, pour in any juices from scallops, and stir in cream.

Bring to a boil and cook until cream sauce is reduced by half, about 10 minutes. Turn off heat and let cool for 1 minute. Quickly whisk egg yolk into cream sauce to combine. Transfer skillet to a cutting board and stir in cayenne, 2 tsp tarragon, and lemon zest into sauce.

Divide mushroom mixture into scallop shells, spreading mushrooms out to cover bottom of shells; place 3 scallops onto each portion. Spoon cream sauce over scallops to coat; let sauce drizzle into mushrooms. Sprinkle with Gruyere cheese and paprika or cayenne.

Turn on broiler to high. Crinkle aluminum foil on a baking sheet to keep the shells level. Broil about 10" from heat until bubbling and cheese is slightly browned, 5 minutes. Remove from oven. Garnish each with 2 crossed tarragon leaves and serve.