Halve and pit avocados. Mash flesh with a fork. Stir in tomatoes, onion, lime juice, hot sauce and salt to taste. Cover with plastic wrap touching dip; refrigerate for up to 3 hours.
Cut a half inch from top of bread and an inch from bottom. Scoop out most of soft interior, leaving 1/2 -inch-thick sides.
Arrange pretzels and peppers to resemble logs and flames on a platter. Fill bread with dip; place on top. Serve immediately.