For best flavor, let the dip rest even longer than an hour if you can, as the seasoning penetrates the corn and cheese over time; always drain Rotel and corn thoroughly to prevent a watery texture, and if the dip still seems loose after chilling, stir in a bit more shredded cheese. Adjust the heat level by choosing mild, original, or hot Rotel and controlling how much jalapeño you use, and feel free to swap part of the cheddar for pepper jack for extra spice. This dip can be made a day ahead, stored chilled, and stirred before serving, but avoid freezing since the dairy can separate. Serve it very cold for the best texture, and keep it on ice or return it to the fridge after 2 hours if serving at a party for food safety.