You can tweak these tuna bakes a bunch of different ways without losing the simple, three-ingredient spirit. For extra flavor, use a flavored tuna (like lemon pepper or jalapeño) instead of plain; it technically doesn’t add ingredients to your prep, but it changes the taste. Swap in a different melty cheese if cheddar isn’t your favorite—Monterey Jack, Colby Jack, or pepper jack all work and still give you those golden, crispy edges. If you’re okay bending the 3-ingredient rule, a pinch of garlic powder, onion powder, or dried parsley stirred into the mixture adds a little “Grandma’s secret ingredient” vibe. You can also stir in a spoonful of finely grated Parmesan for even more savory depth. For mini meal-prep, double the batch and store leftovers in an airtight container in the fridge for up to 3 days; reheat on a foil-lined tray at 350°F (175°C) for 5–7 minutes to re-crisp the cheese. Food safety notes: Always drain the canned tuna very well and keep it refrigerated until you’re ready to mix. Don’t leave the tuna mixture sitting out at room temperature for long periods; mix, scoop, and bake promptly. Bake until the centers are hot and the eggs are fully set—this is especially important if your oven runs cool. Leftovers should be cooled, then refrigerated within 2 hours and reheated only once for best quality and safety.