Save The rain was coming down hard last Tuesday when I decided this was the only thing that would fix a gray afternoon. I'd been experimenting with adding crispy onions to everything from burgers to salads, but it took one particularly desperate midnight snack to realize they belonged in grilled cheese. Something about that sweet-savory crunch cutting through all that melted cheese just works.
My sister texted me at 2am that night asking what I'd made because the smell had apparently drifted down the hall. She showed up ten minutes later in pajamas, and we stood over the stove eating them straight from the pan. Now it's become our unofficial tradition for movie nights, rainstorms, or any moment that needs intervention.
Ingredients
- Small yellow onion: Thinly sliced gives you those delicate strands that fry up into golden lace
- All-purpose flour and cornstarch: The combo creates a coating that stays crispy instead of getting soggy
- Buttermilk: Adds tang and helps the coating cling to every onion strand
- Sourdough or white bread: Something substantial enough to hold all those layers without falling apart
- Sharp cheddar: Brings the bold flavor that stands up to those assertive crispy onions
- Mozzarella: Creates those gorgeous cheese pulls and balances the sharp cheddar
- Unsalted butter: Softened spreads evenly and gives the exterior that perfect golden finish
Instructions
- Make the crispy onions:
- Whisk flour, cornstarch, salt, pepper and paprika in one shallow bowl, pour buttermilk into another. Dip onion slices in buttermilk, then coat them in the flour mixture, shaking off any excess. Heat an inch of vegetable oil in a skillet over medium-high heat until shimmering. Fry the onions in batches until they're golden and smell incredible, about 2 to 3 minutes per batch. Drain them on paper towels and try not to eat them all before assembling.
- Build your sandwich:
- Butter one side of each bread slice generously. Place two slices buttered-side down on your work surface. Sprinkle half the cheddar and mozzarella over each, pile on those crispy onions, then cover with the remaining cheese. Top with the other bread slices, buttered-side up, so everything is nestled between layers.
- Grill to perfection:
- Heat a nonstick skillet or griddle over medium-low heat. Cook the sandwiches for about 3 to 4 minutes per side, pressing gently with your spatula. You want the bread deeply golden and the cheese melting through the onions. Let them rest just a minute before cutting so the cheese sets slightly.
Save Last month I made these for a friend who swore she hated grilled cheese because it was too basic. She took one bite, went silent for a full minute, then asked if I could teach her how to make the crispy onions for everything. That's when I knew this wasn't just a recipe anymore.
Cheese Choices That Work
I've played around with different combinations and found that gruyère adds a nutty sophistication while pepper jack brings a gentle heat. The key is having at least one melting cheese like mozzarella and one with personality like cheddar. Provolone works beautifully if you want something milder.
Make Ahead Magic
You can fry a double batch of onions and store them in an airtight container for up to three days. They actually get better after sitting overnight because the flavors deepen. When you're ready to make sandwiches, just rewarm them briefly in a 350°F oven to restore their crunch.
Serving Ideas That Make It Complete
A swipe of Dijon mustard on the interior bread adds a sharp counterpoint to all that richness. Some tomato soup on the side turns this into a proper meal. A handful of arugula tucked inside adds a fresh, peppery bite that cuts through the cheese.
- Try adding a few pickle slices for brightness
- A drizzle of hot honey takes this into sweet-spicy territory
- Cut these into small squares for the best appetizer you'll ever serve
Save Sometimes the simplest comfort food just needs one perfect twist to become unforgettable. This is that twist.
Recipe FAQs
- → Can I use store-bought fried onions?
Yes, store-bought crispy fried onions work perfectly as a time-saving shortcut. They'll still provide that delicious crunch and savory flavor without the extra frying step.
- → What type of bread works best?
Sourdough bread provides excellent structure and tangy flavor, but sturdy white bread, country loaf, or even Texas toast all work well. Avoid very soft bread that might become soggy.
- → How do I prevent the sandwich from getting soggy?
Ensure your crispy onions are well-drained on paper towels before assembling. Also, butter the bread generously and cook over medium-low heat to allow the cheese to melt completely without burning the bread.
- → Can I add other ingredients?
Absolutely! Dijon mustard, tomato slices, bacon bits, or sliced jalapeños make excellent additions. Just keep the layers thin to maintain proper melting and structural integrity.
- → What's the best cheese combination?
Sharp cheddar provides bold flavor while mozzarella delivers superior melt and stretch. Gruyère, Swiss, or provolone also work beautifully for different flavor profiles.
- → Can I make the crispy onions ahead?
Yes, fry the onions up to a day in advance and store in an airtight container at room temperature. Recrisp them briefly in a 350°F oven for 5 minutes before assembling.