Prep your ingredients. Julienne the onion and green bell peppers and set aside.
Season the steaks with salt.
In a cast iron pan, place 2 tablespoon of avocado oil (any neutral oil). Once hot, sear your steaks until medium rare. 3-4 minutes each. Rest for 10 minutes.
Remove excess oil using paper towels.
In the same pan, add the onion and green bell peppers. Add water and cover with a lid. The steam will cook down the onion and bell peppers more quicker. 5 minutes.
Uncover the pan and let the liquid cook down. Cook the vegetable to your liking.
Slice the steaks into thin pieces.
Start assembling the sliders. Slice the rolls in half.
Make your Horseradish Mayo Sauce. Combine the mayonnaise and horseradish. Spread it all over the top and bottom of the sliders.
Place 4 slices of cheese on the bottom part. Layer it with green bell pepper and onion mixture. Then the steak and cheese.
Bake it at 350 degrees for 10 minutes or until the cheese has melted.