A large, flat pan or skillet are great alternatives to a griddle. Similar to a griddle, you can use these pans for a variety of cooking tasks, from frying ingredients to toasting homemade buns. You can also use them to grill meats and stir-fry food items like rice or asparagus.
To emulate the surface area of a griddle, be sure to use cookware that's large enough to fit all of your ingredients.