Preheat the air fryer. Set it to 360°F (182°C) for 3 minutes. Lightly spray the basket to prevent sticking.

Cut the hearts. Use the heart-shaped cutter to punch out two hearts per sandwich. Gently press so the edges are clean. Save the bread scraps for croutons or French toast sticks.

Build the filling. For savory, spread a thin layer of mayo or butter on the outside of each heart. Add cheese and protein on the inside, plus any veggies. Season lightly. For sweet, spread Nutella or peanut butter and add thin strawberry or banana slices. Do not butter the outside for sweet fillings unless you want a richer, toastier finish.

Seal the edges (optional but helpful). Press the edges together with your fingers. For extra seal and color, brush the outside edges with a light egg wash.

Air fry the first side. Place sandwiches in a single layer. Cook at 360°F (182°C) for 3–4 minutes until lightly golden.

Flip and finish. Carefully flip with tongs. Cook another 2–3 minutes until the bread is golden and the cheese is melted. Total time: 5–7 minutes.

Rest briefly. Let the sandwiches sit for 1 minute to set the cheese and keep the shape intact.

Serve. Enjoy as is, or add a dip like tomato soup, honey-mustard, or warm berry compote for sweet versions.