Preheat the oven to 400°F and prepare a baking sheet by covering it with a layer of foil.
Rinse the shrimp, and clean and devein as needed. In a medium bowl, toss the shrimp with 1 tablespoon olive oil, 2 teaspoon salt, and ½ teaspoon pepper. Spread the shrimp out on the baking sheet in an even layer and roast for 6-8 minutes. Once cooked through, set aside and keep warm.
Once the shrimp is in the oven, heat 1 tablespoon oil in a large wok (if you don’t have a wok, a non-stick skillet is just fine). Sauté the cabbage over medium-heat, until the edges are browned (about 4 minutes). Reduce the heat to medium low and cook the cabbage until tender (another 4 minutes). Remove the cabbage to a large bowl and carefully wipe down the skillet with a dry paper towel to remove any browned bits.
While the cabbage is cooking, prepare the noodles as directed by the package instructions. Once ready, add the cooked noodles to the bowl of sauteed cabbage and toss with 2 teaspoons of sesame oil.
Heat a tablespoon of vegetable oil to the same wok (or skillet) you used for the cabbage over medium heat. Add the celery, fennel, ginger, and red pepper flakes. Toss together and sauté for 3 minutes.
Pour the mirin, tamari (or soy sauce), and lime juice into the wok, and add back in the cabbage/noodle mixture. Cook everything for 5 minutes, stirring often. Add the oven roasted shrimp, and sauté an additional 45 seconds to bring the whole dish together. Remove the pan from heat.
Heap piles of Spicy Shrimp Udon Noodle Stir Fry into individual bowls, and sprinkle with toasted sesame seeds and chopped chives. Serve!
Low FODMAP Optional: This dish is mostly FODMAP-friendly, omitting onion and garlic from the recipe without sacrificing flavor. For a strict low FODMAP diet, substitute gluten-free rice noodles for the Udon noodles and reduce the celery to less than 5cm stalk (or omit altogether).