Hamburger｜Party Kitchen

Finely chop the two onions, slice the tomatoes into round slices of about 1 cm, and cut the other vegetables into pieces that are suitable for hand blending.
Soak one chopped onion in water for 10 minutes, lightly salt and soak in water for 20 minutes.

Cut onions, carrots, celery, and canned tomatoes into a suitable size and put them in a hand blender to make a paste.
Heat salad oil and chopped garlic in a frying pan over medium heat to make it fragrant, add minced pork and fry.
Add bouillon and simmer over low heat for about 20 minutes while mixing.
Add the ingredients of the remaining sauce, turn off the heat after boiling, and adjust the taste with ketchup.

Heat salad oil (not included) in a frying pan over medium heat, add chopped onions and fry until clear.
Transfer to a plate to remove the rough heat and let it cool.

Put the stir-fried onions and the remaining ingredients (B) in a bowl and mix well until sticky.
Mold into a circle with a diameter of about 6 cm.

Heat 2 tablespoons of salad oil (not included) in a frying pan, line up the hamburger steak and bake on medium heat.
Shake the frying pan from time to time, and when the hamburger is browned, turn it over with a spatula.
Cover and cook over low heat for about 5 minutes.

Place the hamburger on the toaster-baked buns, put a little mustard, about 3 laps of mayonnaise, and put the onion, sauce, tomato, and buns that have been exposed to water in that order.