How to Make It
Combine all of the ingredients in a mini-processor, blender or mortar and blend or grind to a paste.
Heat the oil in a small saucepan until shimmering. Add the serranos and sauté over moderate heat until the skins start to brown and blister, about 2 minutes. Transfer to paper towels. Add the garlic to the pan and cook over low heat until golden, 4 to 6 minutes. Transfer to paper towels and let cool.
Using a small knife, make six or seven 1-inch horizontal incisions along the edge of each steak. Stuff each steak with 4 garlic cloves and 2 to 3 serranos.
Light a grill or preheat the broiler and position a rack nearest the heat source. Season the steaks with salt and pepper and grill or broil for 4 to 5 minutes per side for medium rare meat. Serve the steaks at once with the lime relish.