Toasted Parmesan Polenta Crackers with Salad

Brush a baking sheet with oil and brush a large sheet of parchment paper with oil. Peel onions and finely chop. Heat oil in a pan and fry onions until tender. Gradually sprinkle cornmeal into boiling broth, stirring constantly. Whisk until thickened. Stir lemon zest and juice into polenta. Season with salt and pepper. Spread polenta mixture in a layer about 1 cm (approximately 1/3 inch) thick on parchment paper. With a cookie cutter, cut out star shapes and place on a greased baking sheet. Sprinkle stars with parmesan. Toast polenta stars very briefly under broiler until cheese is toasted, watching carefully. Rinse lettuce, spin dry and tear or cut into bite-size pieces. Season vinegar with salt, pepper and sugar. Peel garlic and squeeze through a press into mixture. Gradually drizzle olive oil into vinaigrette, whisking constantly. Toss lettuce and vinaigrette in a bowl and serve immediately with polenta crackers.