Choose the right pan. Use a nonstick skillet or seasoned cast-iron pan for even heat. Set it over medium-low heat.

Prep the bread. Lightly pre-toast the gluten-free bread in a toaster for about 30–45 seconds, just until it’s a bit drier to the touch. This helps prevent gumminess and keeps the sandwich crisp.

Butter and mayo. Spread a thin layer of butter on one side of each slice. For extra color and crunch, mix a little mayo with the butter and spread that on the outside faces.

Build the sandwich. Place one slice, buttered side down, on the cutting board. Add the shredded cheese evenly, leaving a small border around the edges. Season with a pinch of salt and pepper if desired. Top with the second slice, buttered side out.

Warm the pan. Add a small pat of butter or a quick swipe of oil to the pan. When it gently sizzles (not smokes), it’s ready.

Cook low and slow. Place the sandwich in the pan. Cook for 3–4 minutes on the first side, pressing lightly with a spatula. If the bread browns too fast, lower the heat.

Flip carefully. Slide the spatula under the sandwich and flip in one confident motion. Cook for another 3–4 minutes. The cheese should start to ooze at the edges and the bread should be golden.

Steam-melt trick (optional). If the cheese isn’t fully melted, lower the heat, cover the pan for 30–45 seconds, then uncover to re-crisp for another 20 seconds.

Rest and slice. Transfer to a cutting board and let it rest for 1 minute so the cheese sets slightly. Slice diagonally for classic triangles.

Serve hot. Enjoy as is or with tomato soup, a side salad, or pickles for contrast.