1 pound boneless beef chuck roast, cut into 1/2" pieces
Freshly ground pepper
1 large white onion, finely chopped
4 garlic cloves, finely chopped
2 teaspoons ground cumin
1 teaspoon dried oregano
1 (12-ounce) bottle lager
1/2 acorn squash, scrubbed, sliced into thin wedges, then into 1" pieces
2 tablespoons fresh lime juice
2 tablespoons raw pumpkin seeds (pepitas)
Sliced red onion (for serving)
YIELD 4 servings
Toast chiles in a dry small skillet over medium-high heat, turning occasionally and pressing down to help them make contact with the pan, until darkened in color and beginning to soften, about 3 minutes. Transfer to a bowl and cover with 2 cups boiling water; let sit 30 minutes to soften. Drain; remove seeds and stems. Purée chiles and broth in a blender until smooth, about 1 minute.
Once chiles have soaked 10 minutes, heat 1 tablespoon oil in a large heavy pot over medium-high. Season beef with salt and pepper and cook, stirring occasionally, until browned all over, about 5 minutes. At this point, quite a bit of liquid will have accumulated; continue to cook until it has evaporated, about 3 minutes. Transfer beef to a plate.
Add 1 tablespoon oil to pot, then white onion and garlic; season with salt and pepper. Cook, stirring often, until softened, 6–8 minutes; onion juices will help loosen anything left on bottom of pot. Add cumin and oregano and cook, stirring, 1 minute.
Return beef to pot and add beer. Bring to a boil, reduce heat, and simmer, stirring occasionally, until almost completely reduced, about 4 minutes. Add chile purée, season with salt and pepper, and bring to a boil. Reduce heat and simmer until liquid is slightly thickened and meat is tender, 20–25 minutes. Add squash; cover and cook until tender, 10–15 minutes. Stir in lime juice.
Meanwhile, preheat oven to 350°F. Toss pumpkin seeds and remaining 1 teaspoon oil on a rimmed baking sheet; season with salt. Bake, stirring occasionally, until golden brown, 8–10 minutes. Let cool.
Serve chili topped with sour cream, avocado, red onion, and toasted pumpkin seeds.