Wash and dry all produce. Adjust rack to middle position and preheat oven to 425 degrees. Halve, peel, and finely dice onion. Pick and finely chop enough sage leaves to give you 1 TBSP. Mince or grate garlic.

Toss squash on a baking sheet with chopped sage, a drizzle of olive oil, and a pinch of salt and pepper. Roast in oven until tender and browned, about 30 minutes, tossing halfway through. Meanwhile, bring 3 cups water and stock concentrate to a gentle simmer in a small pot.

Heat a drizzle of olive oil in a large pan over medium heat. Add onion and cook, tossing, until softened, 5-6 minutes. Add garlic and cook until fragrant, about 30 seconds. Season with salt and pepper.

Add rice to pan and toss until grains are translucent, 1-2 minutes. Pour stock into pan 1/2 cup at a time, stirring after each addition. Allow rice to absorb stock before adding more. Continue until grains are al dente, 25-30 minutes— risotto should be thick but not stiff and grains should have a little bite to them.

Once risotto is done cooking, stir squash into pan, followed by 1 TBSP butter and half the Parmesan. Season with salt and pepper.

Divide risotto between plates. Garnish with pepitas and remaining Parmesan and serve.