TOMATO GALETTE
2 large onions, thinly sliced3 tablespoons olive oilCrust dough for 1 galette3 tablespoons Dijon mustard1 cup Gruyere, white cheddar or kashkaval cheese, shredded4 large heirloom tomatoes, cut in thick slicesSalt and pepper to taste1 tablespoon Parmesan cheese1 egg, beaten1/4 cup basil, thinly chopped Sauté onions in olive oil over low flame for 30 minutes until…