Peel the potatoes and place them in a large pot with the chopped onion. Cover generously with water, add salt, and bring to a boil.

Cook for about 10 minutes, then add the apple pieces. Continue cooking until the apples are soft and the potatoes are tender.

Drain well and let the potatoes and apples steam dry for a few minutes.

Add a pat of butter and mash everything together until creamy. If needed, add a splash of milk to make the mash a little smoother.

While the potatoes are cooking, fry the bacon until browned and crispy. Transfer to a paper towel-lined plate to drain.

Cut the cheese into smaller pieces. The smaller pieces are easier to handle when coating and frying, but make sure they aren’t too thin or the cheese will melt too quickly.

Beat the egg in a shallow bowl. Dip each piece of cheese into the beaten egg and then coat with sesame seeds. Repeat to create a fairly thick coating. Some of the sesame seeds will inevitably fall off, which is completely normal.

Heat a skillet over high heat with a little olive oil and butter. Quickly fry the cheese until the sesame seeds are golden brown and the cheese has just started to melt.

Serve the hete bliksem topped with crumbled crispy bacon and the sesame-crusted fried cheese.