Heat a pan to medium heat and add olive oil. Add serranos and onion and cook about 5 minutes to soften.
Add garlic and cook another minute, until fragrant. Cool and add to a mixing bowl.
Add crab meat, cheeses, Panko, Old Bay, salt, and about half of the fresh basil. Stir.
Heat oven to 350 degrees.
Slice each sweet pepper in half lengthwise and scoop out the innards.
Stuff each pepper with the crab mixture and sprinkle with dried basil.
Set onto a lightly oiled baking sheet. Bake 20-25 minutes.
While stuffed peppers are baking, add butter, lemon juice and remaining basil to a small pot. Heat on low until butter melts. Swirl.
Drizzle the Lemon-Basil Butter over the stuffed peppers and serve.