You can lessen the spiciness simply by using less habanero pepper. 1/2 of a chili is a good place to start if you have concern about overall spiciness. Note this sauce will become spicier as it ages. If you plan on keeping it for a few weeks, prepare for extra spiciness as the flavors meld and the habanero ages in the sauce Use gloves when handling habanero peppers. These are extra-hot chilies that can cause severe chili burn. Know your options for treating the burn if it happens.