How to Make It
In a large cast-iron skillet, heat 2 tablespoons of the canola oil. Add the bell peppers and onion and season with salt and pepper. Cook over moderately high heat, stirring occasionally, until softened and browned in spots, about 8 minutes. Transfer the pepper mixture to a small bowl.
Wipe out the skillet and heat the remaining 1 tablespoon of canola oil in it. Season the steak with salt and pepper. Add the steak and cook over high heat, stirring occasionally, until browned and just cooked through, about 3 minutes. Transfer the steak to a small bowl.
Wipe out the skillet, add the half-and-half bring just to a simmer over moderate heat. Whisk in both cheeses in small handfuls until completely melted and the queso is very smooth, about 5 minutes. Top the queso with the steak and pepper mixture. Keep warm over very low heat and serve immediately with the toasted hoagie roll slices.