Zucchini and Chorizo Cheese Toast

butter

red onion, peeled and shaved into thin slices

ground pork chorizo

loaf ciabatta bread or french bread baguette

medium yellow squash, shaved into 2½ to 3-inch lengths

medium green zucchini, shaved into 2½ to 3-inch lengths

garlic salt

aged Gouda cheese, shredded

kosher salt and freshly ground black pepper

fresh thyme leaves