Preheat oven to 325°
Pat frog legs dry with paper towels. Using a sharp knife, split the saddle connecting the pairs of legs. Season frog generously with salt and pepper.
Melt butter in a skillet or fry pan over medium-high heat. Fry frog legs in batches, flipping once, until both sides are golden and meat is just cooked through (about 2 minutes per side. Be careful not to overcook, or the meat will turn rubbery). Remove from heat and let rest. Once they are cool enough to handle, pull meat from the bone and shred. Set aside.
Warm refried beans in a small sauce pan on the stove, or in a bowl in the microwave. The beans do not need to be hot, just warm enough to pour and spread easily.
Layer tortilla chips on a baking sheet or ovenable serving platter (if you are using a baking sheet and planning to transfer to another dish for serving, laying down a sheet of parchment paper first will make the transfer much easier).
Spread the beans as evenly as possible across the top layer of tortilla chips. Scatter shredded frog meat and pickled peppers on top, then sprinkle liberally with Chihuahua cheese. Bake at 325° for 10-15 minutes, until cheese is melted and bubbly.
Remove from oven. Sprinkle with diced avocado and fresh cilantro, then drizzle with sour cream and tomatillo pasilla salsa.
Serve immediately.