To pan-fry paneer so it's perfectly golden and not tough or rubbery, use medium heat, cook it quickly until it turns golden, and you can even marinate it for a little while.
Paneer is a fresh cheese, and like many fresh cheeses, it can get tough very quickly if you overcook it or blast it with super high heat for too long. The trick is to get that lovely golden-brown exterior without drying out the inside. Start by patting your paneer cubes or slices thoroughly dry – this helps it sear nicely. Heat a non-stick or cast-iron pan over medium heat with a tablespoon or two of oil or ghee. Once the oil is shimmering, add your paneer in a single layer, making sure not to overcrowd the pan. Cook for just 1-2 minutes per side, or until each side has that beautiful golden color. As soon as it hits that perfect shade, take it right off the pan. For extra flavor and to help keep it moist, you can marinate the paneer briefly (15-30 minutes) in a mix of yogurt, ginger-garlic paste, and your favorite spices before frying.
If your paneer tends to be a bit dry, try soaking it in warm water for 15-20 minutes before you fry it. This can really help keep it softer inside!