Marinate: In a bowl, whisk curd, mustard oil, and all spices. Add paneer cubes and coat well. Let it rest for at least 30 minutes.
Sear: Heat a non-stick pan or grill pan. Sear the paneer cubes on medium-high heat for 2 minutes on each side until you see golden-brown char marks.
Prep the Buns: Slice the mini buns in half. Apply a little butter and toast them on the pan until light gold.
Assemble: * Spread a generous layer of Mint-Mayo on the bottom bun.
Place one Paneer Tikka cube on top.
Add a fresh onion ring and a sprig of cilantro.
Close with the top bun and secure it with a fancy bamboo skewer or toothpick.
Serve: Arrange them on a platter with extra green chutney on the side.