Use a spiralizer tool to cut the zucchini into thick curly noodles. While spiralizing, use your hands to break the zucchini noodles into manageable lengths (no longer than about 8-10 inches). Mound the zucchini noodles evenly onto a steamer basket.
Using the saute function, heat the pressure cooker and add the ground beef. Break the meat into crumbles and cook until the meat is no longer pink.
In a small bowl, combine the soy sauce, sesame oil, brown sugar, garlic, ginger, chili peppers and water. Stir this sauce into the beef and continue cooking for 1-2 more minutes, until the garlic and ginger are fragrant.
Add the sliced carrots and baby spinach, and toss together with the beef. Place the steamer basket of zucchini noodles directly on top of the beef and vegetable mixture.
Close the lid, with the valve set to sealing position. Cook on low pressure for 0 minutes.
When the cooking time is complete, carefully open the valve to manually release the pressure immediately.
In a large serving dish or individual portion bowls, gently toss together the zoodles with the seasoned beef and vegetables. Top with sesame seeds and thinly sliced green onions.