Marinated Steak with Mushrooms Walnuts & Spring Onions

1 kg flat iron steak, cut in 4 even portions
1 tbsp olive oil, plus ¾ cup for vinaigrette
1 tsp garlic powder
1 tsp onion powder
2 tsp SIDS SALT & PEPPER
4 cups portobello mushrooms, sliced
1 tbsp butter
2 cloves of garlic, sliced thinly
1 cup walnuts, roughly chopped
VINAIGRETTE:--
½ tsp Dijon mustard
¼ cup SIDS LOW SUGAR RASPBERRY VINEGAR
2 spring onions, chopped

In a sealable bag, add the steaks, 1 tablespoon of oil, garlic powder, onion powder, and SIDS SALT & PEPPER. Shake so all the ingredients are mixed well. Leave to marinate for at least 30 minutes.
Preheat a BBQ to at least 180ºC. Grill each steak for between 4-5 minutes turning every 15 seconds. Remove steaks to rest for 10 minutes.
Add mushrooms and butter to the BBQ hot plate, letting the butter melt on the mushrooms. Remove mushrooms once they caramelise.
On the same hot plate, grill garlic slices until they are caramelised. Make sure to keep an eye on them so they don’t burn. Add the walnuts and toast then set aside.
VINAIGRETTE: combine the oil, mustard, salt and SIDS LOW SUGAR RASPBERRY VINEGAR in a jam jar with its lid and shake well until fully combined. Add half of the spring onion to the jar and shake to combine.
To serve, slice the meat across the grain and place on a serving plate, add mushrooms to the side and lace generously with fried garlic and remaining spring onions. Pour vinaigrette generously on top and enjoy.