Whisk the sauce ingredients in a large liquid measuring cup.
In a large sided skillet brown the chicken, breaking it up into small pieces as you go. Season the chicken with salt and pepper as desired.
Boil the noodles until softened, about 2-3 minutes. Drain and set aside.
To the skillet with the chicken, add the sauce. Bring to a simmer (it will slowly be thickening). Once simmering stir in the cooked noodles, and spinach. Stir to combine. Remove from heat and top with cilantro and green onions. Serve immediately.
Notes
Make Ahead: This recipe comes together so quickly, there’s not much to prep ahead of time. However, you can make this quicker by prepping your sauce in advance (3-4 days) and keeping it in the fridge, and also by either pre-cooking your ground chicken or using leftover protein from another meal. Leftover rotisserie chicken would work great. Storing: Store leftovers in an airtight container in the fridge for 3-4 days. Reheat either in the microwave or in a pan on the stovetop. Freezing: I would not recommend freezing this prepared dish. I believe that once it thawed, the noodles would be extremely mushy and the fresh ingredients (spinach, green onions, cilantro) would not thaw well either.