Preheat your oven to 350 degrees. Line a baking tray with parchment paper and brush it with olive oil.
Lay out your fillets on the tray. Flip each one over to sprinkle some salt on the underside, then lay them back down, right side up.
Brush the tops of the fillets with olive oil.
Sprinkle the tops with salt, then with paprika.
Cut your lemons into rounds, then lay the lemon rounds down the length of the fish. Sprinkle any herbs you would like to add.
Add little pats of butter over your fillet. I usually add a little dime-sized pat between each lemon slice and then maybe on the ends or edges if the fillet is big enough.
Bake at 350 degrees for 25 minutes.
Remove the lemon slices and serve immediately.