Burger patties

• Mix the ground beef with worcestershire sauce in a bowl.
• Add a bit of salt and pepper.
• Weigh the patties at 75 grams each.
• Form them into burger patties, very flat and press them extra flat in the middle. This prevents them from shrinking.
• Put oil or butter (or both) in the pan.
• Fry them on high heat (11 out of 14 on my stove) for 2-3 minutes on each side.
• When you flip the patty, place a slice of cheese on top so it melts.
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• I use an immersion blender for this recipe. If you don't have an immersion blender, you can whisk it by hand, but then you should only use the egg yolk instead of the whole egg.
• Put egg, salt, vinegar/lemon juice, mustard in the immersion blender cup. Grate the garlic clove in and add the oil.
• Place the immersion blender all the way at the bottom of the cup and blend at full speed.
• You will see the bottom start to thicken, so slowly move up until everything turns into mayonnaise.
• Season to taste with salt and pepper.
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• Finely chop cornichons and red onions.
• Rinse your lettuce and dry it well with a clean dishcloth.
• When the patty is done, cut your spiced buns in half and place them cut side down. Fry them for a minute or two until they get crispy. You can also use a toaster for this.
• Assemble your burger, making sure to include a bit of everything. For example, start with French mustard at the bottom, a lettuce leaf on top, then onions, cornichons, patty with cheese, and ketchup in the top bun.
• Enjoy your meal.