2 pounds fresh salmon (about 2 fillets)
4 to 5 Meyer lemons
2 tablespoons unsalted butter
Kosher salt and fresh ground pepper
Aluminum foil or parchment paper
Preheat oven to 375 degrees.
Prepare fennel by removing top stems to where stem meets bulb. Save leafy fronds for garnish. Thinly slice or shave bulb diagonal angle. Set aside.
On large rimmed baking sheet, place large sheet of aluminum foil, shiny side facing down. Place first salmon fillet on aluminum foil and squeeze juice of 1 lemon on top.
Take another lemon and slice into thin rounds; arrange slices on top of fish. Place 1/2 teaspoon butter underneath each slice of lemon (add more lemon and/or butter as needed per size of fillet.) Arrange fennel slices on top of lemon-covered fish. Sprinkle with salt and pepper. Fold sides of aluminum foil to create tent and crimp edges of packet to seal. Repeat with second fillet.
Bake salmon packet on baking sheet 18-22 minutes, depending on thickness of fillets. Open foil packet and remove fish to plate. Drizzle liquid from bottom of packet on top of salmon. Garnish with chopped fennel fronds.