Broil onions and ginger for 5 minutes, or until they begin to char. In a sauté pan over high heat, toast the coriander, peppercorns, cloves, and star anise until fragrant.
To start the stock, add the onion, ginger, toasted spices, dried mushrooms, garlic, chile pepper, basil, cilantro, and mint to a large stock pot. Bring to a boil, then lower heat to a simmer. Simmer, uncovered, for 1 to 1 1/2 hours or until the stock is dark and golden in color.
Strain, discarding the solids. Stir in the fish sauce to taste. Use immediately, or chill and freeze to use another time.
To prepare the soup, soak the noodles in warm water for 30 minutes, or until soft. Drain and divide into serving bowls.
Blanch the snap peas, bok choy, and mushrooms in boiling water for 3-4 minutes, or until vibrantly colored and just cooked. Drain and divide between the serving bowls.
Ladle the stock into each bowl, over the vegetables and noodles. Top with Thai basil, jalapeño, lime wedges, sriracha, and hoisin, as desired.