Butternut Squash Gratin with gruyere

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[...]

2 tablespoons unsalted butter 3 lbs butternut squash, peeled,seeded and cut into cubes 1 cup water 1 clove garlic , minced 1 cup creme fraiche salt & freshly[...]