Place a large stock pot over medium heat. Add the onion wedges, ginger, garlic, cinnamon, star anise, cloves, cardamom, and coconut oil. Saute the onions and spices for about 10 minutes, stirring to brown the onions on all sides.
Pour in the water, fish sauce, sugar, salt, and turmeric. Then add the chicken thighs and bring to a simmer. Lower the heat if needed, and simmer for 30 minutes. (P.S. Fish sauce smells like moldy feet while cooking, but tastes amazing! Don't worry about the aroma, and don't skip it.)
Use a skimmer to pull all the chicken, onions, and spices out of the broth. Reserve the chicken thighs and discard everything else. Chop the chicken thighs into small pieces and add back to the broth.
Meanwhile, use a spiralizer to cut the zucchini into noodles. Chop and prep all other garnishes.
When ready to serve, place a handful of "zoodles" into each bowl. Ladle the chicken pho soup into each bowl. Then let each person garnish their own bowl with basil, sprouts, lime, scallions, jalapeños, and cilantro.
NOTE: We usually set out chili-garlic sauce to spice up our bowl of pho, but the jalapeños will definitely do the trick!