Preheat the oven to 400 degrees.
Prep the steak: Combine the cumin, adobo, granulated garlic, paprika, salt and pepper and rub the steak on both sides. Let sit for 20 minutes on your counter.
Make the sauce: Place the cilantro, garlic, and lime juice in a food processor and pulse to combine. Stream in the olive oil and season with salt and pepper to taste. Pour into a container and set aside.
Make the steak: In a large frying pan over medium-high heat, sauté the onions, garlic, and bell peppers until golden brown. Season with salt and pepper.
Allow an ovenproof pan to heat up over medium-high heat. Once hot, sear the steak in safflower oil on both sides for 3–4 minutes per side. Then place in the oven until your desired doneness.
Remove the steak from the oven, place on a cutting board, cover with foil, and allow to rest for 5 minutes. Once rested, slice the steak against the grain.
Separate the radicchio leaves and arrange on a plate. Stuff with the onion-and-pepper mixture, steak slices, and top with the cilantro sauce. Enjoy!