Butternut Squash Gratin - Vegeterian

2 tablespoons unsalted butter 4 cups thinly sliced onions 1 1/4 lbs butternut squash, peeled,seeded and cut into 1/4 inch slices 1 1/4 lbs yukon gold potatoes[...]

1/4 cup olive oil 4 cups onions , thinly sliced 4 fresh thyme sprigs 2 tablespoons fresh sage , chopped salt & freshly ground black pepper 3 cups butternut[...]

6 cups butternut squash (peeled and cubed into about 1/2-inch pieces) 2 -3 tablespoons butter (can use oil) 2 large leeks , thinly sliced 2 granny smith[...]