Heat the vegetable oil in a skillet over medium heat.

Add the diced onions and sauté for 2–3 minutes, until softened and lightly golden.

Add the ground beef to the skillet, breaking it up with a spatula until nicely browned. . Season with salt, black pepper, garlic powder, and paprika.

Lightly toast the brioche buns under a broiler or in a toaster oven.

Once the beef is cooked through, portion it into piles in the skillet, roughly the size of your rolls.

Place the cheese slices over each pile and let them melt.

Use a spatula to chop the melted cheese into the meat, mixing slightly, then scoop each portion onto a toasted roll.

Spread mayonnaise on the top halves of the rolls.

Top the beef with shredded lettuce, tomato slices, and ketchup if desired.

For the mango lassi, combine mango, yogurt, milk, cardamom, and sugar in a blender. Blend until smooth and creamy. Taste and adjust sweetness as needed.

Serve the chopped cheese sandwiches with carrots and hummus and enjoy with mango lassi.