1. Combine first 2 ingredients and 1 tsp. sugar; let stand 5 minutes.
2. Beat egg, shortening, salt, and 1/4 cup sugar at medium speed with a heavy-duty electric stand mixer until creamy. Add boiling water; stir until shortening melts. Stir in yeast mixture. Stir flour and 1/2 cup crumbs into egg mixture.
3. Place dough in a lightly greased (with shortening) bowl; cover, and chill 8 to 24 hours.
4. Punch dough down. Turn dough out onto a lightly floured surface, and knead 4 or 5 times. Roll to 1/2-inch thickness. Cut dough into rounds with a 1 1/2- to 2-inch round cutter, rerolling scraps twice. Place rolls 1 inch apart on a parchment paper-lined baking sheet, and brush with melted butter.
5. Stir together remaining 1/4 cup cracker crumbs and 1 1/2 tsp. sugar. Sprinkle mixture over rolls. Cover and let rise in a warm place (80° to 85°), free from drafts, 45 minutes to 1 hour or until doubled in bulk.
6. Preheat oven to 350°. Bake, uncovered, 15 to 18 minutes or until golden.