Amazing juicy beef burger

Amazing juicy Beef Burger 

Ingredients:
600 gr of steak beef mince
half a cup of bread crumbs( use the Italian style  Romano cheese mix)
1 egg
2 tsp salt
1 tsp  black pepper
2 tsp burger spices( if you don't have this you can make your own! just mix some white pepper, coriander powder, nutmeg powder, cumin powder,cinnamon, onion powder, in even quantities, and use 2 tsp for this recipe).
1 small onion diced ( optional)
1 tbsp ketchup

2 onions cut in rings and mushrooms for grilling
tomatoes slices
pickles.
7 burger buns
for the coleslaw: 
 300 gr white cabbage
3 medium carrots shredded
1 small onion diced
2 tbsp mayonnaise
2 tbsp sour cream
salt and pepper
Celeri salt ( optional but it gives a nicer taste to your slaw!)

how to make it : 

mix the beef  mince with egg, breadcrumbs and all the other ingredients . make about 6 to  7 patties , place them on a parchment paper and place in fridge while preparing the rest of stuff.
for the coleslaw : cut the cabbage thinly and place in ice water for 30 minutes . shred the carrots. cut the onion, mix all with mayo, salt and pepper, and sour cream. set aside.
cut tomatoes and pickles. cut the onion rings, and mushrooms and grill over the heated pan with a little of olive oil until brown. set aside.
in the same pan, add a spoon of olive oil and grill the meat. till it is well done .
start by putting your burgers together, by adding the sauces you like, such as ketchup, mayo and mustard mix, or chipotle mayo mix for a spicy quick .
i added the coleslaw inside the burgers too!
as well as on the side as extra :)
Enjoy!