1 1/2 pounds red kuri or butternut squash, peeled and cut into 1-inch cubes (3 cups)
1/2 medium onion, coarsely chopped
1 bay leaf
1 medium fennel bulb, cored and cut into thin wedges
1 tablespoon extra-virgin olive oil, plus more for drizzling
Salt and freshly ground black pepper
1 tablespoon unsalted butter
Chopped toasted pecans and small marjoram leaves, for garnish