Select the saute function to medium (if possible) on the Instant Pot. Coat the bottom of the pot with oil, and once hot, add onion. Cook for 2-3 minutes, then toss in ginger and garlic. Once the vegetables are gently browned, about another 3 minutes, select cancel.
Now add in chicken broth, tomatoes, Thai curry paste, sea salt, bell pepper, carrots, and chicken breast. Secure the lid. Select manual, or pressure, and cook on high pressure for 8 minutes.
Use a quick release, and remove the lid. Take out the chicken breast and shred with a fork and knife. Place the chicken back into the pot. Now stir in coconut milk, lime juice, and spiralized zucchini. Let sit for about 10 minutes before serving.
Pour into individual bowls, add salt to taste. Garnish with fresh cilantro (if using).