Combine chicken, garlic, ginger, lemon juice, yogurt, cashew paste, spices, heavy cream and salt in a bowl. Marinate in the fridge for a minimum of 2 hours to overnight.
Heat oven to 450°F, and bake chicken on a lined baking sheet for 10-15 minutes, until slightly charred and cooked through.
Heat oil in a large frying pan over high heat. Add green pepper, onion, and chilies. Sauté for about 1 minute, until slightly softened but still crisp. Remove from heat and add chicken and coriander. Toss to combine.
Heat a large frying pan over medium-high heat. Add tortilla, and toast for 30 seconds on one side. Flip over, and add enough beaten egg to cover surface of tortilla. Allow egg to set, and top with chicken and vegetable mixture.