Pat the steak strips dry with paper towels: Place them in a bowl and season with 1/2 teaspoon of the salt, the smoked paprika, and black pepper. Toss until the seasonings are evenly distributed.

Heat 1 tablespoon (15 ml) of the neutral oil in a 12-inch (30 cm) deep skillet over medium-high heat. When the oil is shimmering, add half of the steak in a single layer. Cook for 1 to 2 minutes without moving it, then turn the pieces and cook for about 1 minute more. The outside should be browned, but the center does not need to be fully cooked yet. Transfer the steak to a clean plate.

Add the remaining steak to the skillet and repeat the searing process. Transfer it to the plate with the first batch. Avoid crowding the pan, which traps steam and prevents browning.

Reduce the heat to medium and add the remaining 1 tablespoon (15 ml) oil. Add the diced onion, bell pepper, and remaining 1/4 teaspoon salt. Cook for 4 to 5 minutes, stirring occasionally, until the onion looks translucent and the pepper has begun to soften.

Stir in the garlic and cook for about 30 seconds, just until fragrant. Add the rinsed, well-drained rice. Cook for 1 minute, stirring frequently, until the grains are coated with oil and the edges look slightly translucent.

Pour in the beef broth and Worcestershire sauce: Scrape the bottom of the skillet to release any browned bits. Bring the liquid to a steady simmer over medium-high heat.

Reduce the heat to low and cover the skillet tightly. Cook for 17 to 19 minutes without lifting the lid. The rice is ready when the liquid has been absorbed and the grains are tender. If the rice is still firm but the skillet looks dry, add 2 tablespoons (30 ml) of hot water, cover, and cook for another 2 to 3 minutes.

Arrange the seared steak and any juices from the plate over the cooked rice. Cover and cook over low heat for 2 to 3 minutes, just until the beef is hot and reaches a safe internal temperature. Whole cuts of beef should reach at least 145°F (63°C), followed by a minimum 3-minute rest. Check the thickest steak strips with an instant-read thermometer when possible.

Remove the skillet from the heat: Sprinkle the cheddar and Monterey Jack evenly over the steak and rice. Cover and let the skillet stand for 5 minutes. The residual heat should melt the cheese into a smooth layer while the steak completes its rest.

Remove the lid and gently fold some of the melted cheese into the top layer of rice, leaving the rest visible on the surface. Sprinkle with the sliced scallions, if using. Serve while the cheese is warm and creamy.