Risotto With Autumn Vegetables without shallots

3 cups vegetable broth or 3 cups chicken broth 2 cups sliced fresh mushrooms 1 medium onion , chopped 2 garlic cloves , minced 2 tablespoons olive oil 1 cup[...]

4 tablespoons unsalted butter 2 tablespoons olive oil 1 medium leek , rinsed well, dried, cut into 1/4-inch dice (white part only) 4 cups chicken broth ,[...]