Heat broiler to high. Bring a medium pot of salted water to a boil. Wash and dry all produce. Mince garlic. Chop spinach until you have 1 very packed cup (2 cups for 4 servings; you might not use all the spinach). Halve lemon; cut one half into wedges. Halve tomatoes. Finely chop parsley.

Once water is boiling, add orzo to pot. Cook until al dente, 7-9 minutes. Reserve 1 cup pasta cooking water, then drain. Heat a large drizzle of olive oil in a large, high-sided (preferably ovenproof) pan over medium-high heat. Add sausage and cook, breaking up meat into pieces, until just browned, 3-4 minutes. (It’ll cook through in the next step.)

Add tomatoes and garlic to pan with sausage. Cook, stirring occasionally, until mixture is fragrant and sausage is cooked through, 2-3 minutes. Stir in half the Italian Seasoning (all for 4 servings); season with salt and pepper. Cook, stirring, until tomatoes begin to break down, 2-3 minutes more. Lower heat to medium.

Stir chopped spinach, stock concentrate, ½ cup reserved pasta cooking water (¾ cup for 4 servings), and cooked orzo into pan. Cook, stirring, until spinach is wilted and mixture is creamy, 2-3 minutes. TIP: If mixture seems dry, stir in more reserved pasta cooking water a splash at a time as necessary.

Stir in mozzarella and a squeeze of lemon juice. Season with salt, pepper, and more lemon juice to taste. (TIP: If your pan isn’t ovenproof, transfer mixture now to a baking dish.) In a small bowl, combine panko, Parmesan, a drizzle of olive oil, salt, and pepper; sprinkle over orzotto. Broil until panko is golden brown, 2-3 minutes. TIP: Watch carefully to avoid burning.

Divide orzotto between plates. Sprinkle with parsley. Serve with any remaining lemon wedges on the side.