To a mixing bowl, add Plain Greek Yogurt (200 gram).
To this add Vegan Mayo (2 tablespoon), Salt and Pepper (to taste), Ginger Paste (1 tablespoon), finely chopped veggies like Bell Pepper (1), Onion (1), Carrot (1/2 cup), Fresh Parsley (1/3 cup), and Jalapeño Pepper (1).
Give it a mix. Keep it aside for now.
Heat Oil (1 teaspoon) in a pan. Temper Black Mustard Seeds (1/2 tablespoon) and once they crackle, add roughly torn Curry Leaf (4) to it. Fry for 10 seconds. Pour this tempering over the yogurt mixture and mix well. The sandwich stuffing is now ready.
Arrange 3 Whole Grain Bread (6 slice) over a tray and spread this yogurt mixture over each slice. Top it with some Lettuce Leaf (3).
Close it like a sandwich using another bread slice and toast it in a pan using Butter (to taste) if desired. You can even grill it in a Panini Maker or toast the bread in a regular toaster first and then make the sandwich. If you like a cold sandwich, consume without toasting.
Cut in any desired shape and serve. This sandwich goes great with some ketchup or chutney.