Bring a pot of salted water to a boil. Cook shrimp until just done, 2 to 3 minutes. Drain; rinse under cold water. Combine shallot, scallions, mint, lime juice, fish sauce and red pepper in a large bowl. Remove 2 Tbsp. to a medium bowl. Combine cabbage and carrot in large bowl; toss with dressing. Add shrimp to medium bowl with 2 Tbsp. reserved dressing; toss.
Arrange cabbage mixture on each of 4 dinner plates. Top with shrimp and serve immediately.