Wash and dry all produce. Halve tomatoes. Trim and thinly slice scallions, separating whites from greens. Trim and quarter mushrooms. Mince or grate half the garlic; halve remaining garlic crosswise.

Heat 1 TBSP butter (2 TBSP for 4 servings) and a large drizzle of olive oil in a large pan over medium-high heat. Add mushrooms, 2 tsp Italian Seasoning (4 tsp for 4), salt, and pepper. Cook, stirring occasionally, until golden brown and tender, 6-8 minutes. Reduce heat under pan to medium.

Add tomatoes, scallion whites, minced garlic, and another drizzle of olive oil to pan. Cook, stirring often, until tomatoes are just softened, 3-5 minutes. Stir in half the stock concentrate and 1/4 cup water (1/3 cup for 4 servings); bring to a simmer. Once simmering, remove pan from heat.

Meanwhile, halve ciabatta as if you were making a sandwich. Toast until golden brown and crispy. Rub cut sides of toasted bread with halved garlic cloves and drizzle with olive oil. Sprinkle with remaining Italian Seasoning and season with salt and pepper. Halve garlic bread on a diagonal to create triangles.

In a medium pot, combine 21/2 cups water (5 cups for 4 servings), remaining stock concentrate, and 1 tsp salt (2 tsp for 4). Bring to a boil. Once boiling, whisk in cornmeal. Reduce heat to low and cook, stirring often, until cornmeal is tender, 8-10 minutes. TIP: If polenta gets too thick, whisk in hot water 1/2 cup at a time.

Heat pan with mushroom ragù over medium heat; stir in 1 TBSP butter (2 TBSP for 4 servings). Cook until mixture is warmed through, 1-2 minutes. Meanwhile, whisk cheese and 2 TBSP butter (4 TBSP for 4) into polenta until melted. Season generously with salt and pepper. Divide polenta between bowls and top with ragù. Sprinkle with scallion greens. Serve with garlic bread on the side.