Begin by generously buttering the outsides of four slices of fresh sourdough bread.

Layer two slices of the buttered sourdough with sharp cheddar cheese, a generous spoonful of kimchi, and gouda cheese.

Place the remaining two slices of sourdough on top, buttered sides facing outwards, and press gently.

Heat a cast-iron pan over medium-high heat and place the assembled sandwiches in it.

Cook for about 5 minutes until the bottom is golden brown and then flip the sandwiches.

After another 5 minutes, ensure both sides are golden and the cheese has melted completely.

Remove from the pan, slice in half, and serve immediately.