To prepare a Spanish hard rolls bolillos baked goods recipe, first you need to prepare your ingredients. First, you'll need your flour, baking powder, sugar, and salt. Then, add your dry ingredients to the wet ingredients and mix them together until they're well combined. Next, heat your oven to 375 degrees Fahrenheit (190 degrees Celsius) and grease your baking sheet with cooking spray. Place the dough in the oven and bake for 20 to 25 minutes or until it's golden brown.