Healthy Mushroom Sandwich

Ingredients:
sourdough bread slices
1 tbsp wood pressed groundnut oil
6-7 garlic cloves
1 onion, chopped
1 tsp sea salt
200 gms mushrooms
1/3 tsp turmeric powder
1/2 tsp black pepper powder
1/2 tsp garam masala
1/4 of capsicum
moringa leaves
juice of half a lemon