For the best taste and texture, it's always ideal to serve waffles as soon as possible after they've been made. However, when you need to prepare them in advance or are serving a large group, here is how you can keep them warm: If you plan to serve your waffles within 30 min or an hour, set your oven to a low temperature, typically between 200°F (93°C) to 250°F (121°C). Position them in a single layer on a wire rack above a rimmed baking sheet. It prevents them from getting soggy. Then, serve them directly from the oven.  If you need to store them for an extended period, it's better to let them cool and then re-crisp them in the oven or toaster when ready to serve.