Preheat oven to 350°. Without separating rolls, cut rolls in half horizontally; arrange bottom halves in a greased 13x9-in. baking pan. Top with half of cheese slices; set aside.
In a large skillet, cook beef and onion over medium heat until beef is no longer pink and onion is tender, 6-8 minutes, break up beef into crumbles; drain. Stir in sloppy joe sauce, brown sugar, soy sauce and pepper. Cook and stir until combined, 1-2 minutes. Spoon beef mixture evenly over rolls; top with remaining cheese. Replace top halves of rolls.
For glaze, stir together butter, brown sugar, mustard, soy sauce and garlic powder. Brush over rolls; sprinkle with sesame seeds and minced onion. Bake, uncovered, until tops are golden and cheese is melted, 15-20 minutes. If desired, top with pickle slices.
Freeze option: Cover and freeze unbaked sandwiches; prepare and freeze glaze. To use, partially thaw in refrigerator overnight. Remove from refrigerator 30 minutes before baking. Preheat oven to 350°. Pour glaze over buns and sprinkle with sesame seeds and minced onion. Bake sandwiches as directed, increasing time by 10-15 minutes, until cheese is melted and a thermometer inserted in center reads 165°.
Test Kitchen tips
Everything seasoning works perfect for sprinkling on top of rolls in place of sesame seeds and dried onion. Just omit the soy sauce in the glaze to account for the salt in the seasoning.
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