Cook Onion & Beef: Heat 1 teaspoon of the olive oil in a large, deep skillet or Dutch oven (recommended) over medium heat. Add the onion, sprinkle with ¼ teaspoon of the salt, and cook until just starting to soften, about 3 minutes.
Add 1 teaspoon of olive oil along with the ground beef and ½ teaspoon of salt. Cook, breaking up with a wooden spoon, until browned and cooked through, about 5-7 minutes.
Add Seasoning: Stir in the Italian seasoning and garlic. Cook for 1 minute, stirring constantly.
Add Orzo & Liquids: Add orzo, tomato sauce, and beef broth. Stir well, scraping up any bits from the bottom of the pan.
Simmer Until Tender: Bring to a low boil, then reduce heat and simmer uncovered for 10-15 minutes, stirring frequently to avoid the orzo sticking to the bottom of the pan, until orzo is tender and most of the liquid is absorbed.
Finish: Turn off the heat, then stir in half-and-half, Parmesan, remaining ¼ teaspoon of salt, and black pepper. Let sit for 2-3 minutes to thicken. Add spinach now if using, and stir until wilted. Serve with additional Parmesan and black pepper if that’s your thing.