First of all, I recommend preparing the burger buns. You can make them at home, following my step-by-step recipe or you can buy them. 

Then cut them in half and spread butter on the cut side.

Heat the grill (or a grill pan) and toast the buns, cut and buttered side down. 

I don't want to toast them both sides, I like the crust soft, you can do it, though, if you want to.

Put them aside and make sure you don't mix them up :) 

If you have bacon, you can fry it in a pan or put in the oven. 

I normally place the sliced bacon on a dried baking sheet and put it in the preheated oven for a few minutes.

Stay close and watch it, it easily gets dry and it might burn. 

Right after removing from the oven, turn the bacon onto paper towels to absorb the extra fat and let cool for a little while. 

Optionally, you can prepare caramelized onions. I do it this way:

- I julienne 5-6 big white onions, fry them in 50g butter and 2 tbsp sugar. I cook them over a medium-high heat for a short while until they start becoming golden caramel, then I let them slowly caramelize over a low heat, as you can see in the picture. Stir periodically and see how the colour and the taste change. 

I liked better the burgers with quick marinated onions, they tasted more fresh and more interesting. 

All I need to do is slice thin a red onion, spread over a pinch of salt, some sugar and 1 tsp apple cider or balsamic vinegar. I massage well with my hands and let for 15 minutes for the flavours to blend.

For the sauce, I recommend "Thousand Island" sauce, you can skip the finely chopped onions (although my girls don't even feel it) or replace it with any other sauce you like. 

It would be a good idea to start preparing the vegetables as well - wash and dry the salad leaves, thinly slice the tomatoes and the pickled cucumbers. 

Prepare the burger patties following my recipe or any other recipe. 

You can also have chicken or vegetarian burgers. 

After you cook the patties on one side and you turn them, put a slice of yellow cheese on top and let it melt a bit. 

As soon as the meat is ready, quickly assemble the burgers, these have to be served while hot and freshly cooked.

So, take the first half of the bun and spread over some sauce.  

The hot patty comes next. 

I noticed that many recipes place the salad leaves at the base. I don't recommend that, they will lose their freshness and crispiness because of the hot meat.

Over the patty you can spread caramelized onions, if you have and if you like.

Next comes the fried bacon and some sauce again.

Then, the sliced pickled cucumbers, marinates onions (if you like) and salad leaves.

The last ones are the tomato slices.

Cover with the other toasted half of the bun and pierce the middle with a bigger wooden toothpick (I use a long barbecue skewer, I break it in half and it fits perfectly for taller hamburgers).

This is meant to keep it all together and prevent the layers from spreading when bitten :) 

Serve the burgers right away, some crispy oven roasted potatoes would go very well together - but, honestly, it might be too much for the belly :) 

Enjoy!