These donut-themed puzzles are a great way to randomly group your students. Simply give each student a single piece of a puzzle and have them find their partners to complete the puzzle.
I use these with lower-level students as a speaking activity on its own. I have students find their partners without showing their pieces to one another. I pre-teach the necessary vocabulary: sprinkles, icing, covered, dipped, etc. and give them a time limit.
If you like the idea of mingling puzzles, but want to combine with a skill, check out these Telling Time Puzzle Task Cards.