On the Scoville scale, which measures the heat of chile peppers, the habanero comes in at the extra-hot zone with a rating of 100,000–350,000 Scoville heat units, or SHU. Despite the hot rating, this salsa won't burn your tongue off. We use enough to keep it spicy without going overboard. That said, you're certainly more than welcome to use more habanero if you can't get enough heat.