Soak noodles in a bowl of warm water for 5 minutes. Bring a large pot of water to a rolling boil. Stir in noodles and bring back to a boil. Cook until tender, 4 to 5 minutes. Drain.
Bring a saucepan of water to a boil. Add shrimp and boil until just opaque, 2 to 3 minutes. Drain.
Heat oil in a skillet over medium heat. Add onion and garlic; cook and stir until onion is translucent, about 5 minutes. Transfer half the mixture to a bowl and set aside. Stir achiote powder into the skillet with the remaining onion and garlic mixture. Add prawns; reduce heat and let simmer until well coated, about 2 minutes.
Heat a large pot over medium-high heat. Saute pork until browned, crumbly, and no longer pink, 5 to 7 minutes. Add the remaining 1/2 of the onion-garlic mixture; season with salt and pepper. Add cream of chicken soup; stir until well mixed. Add chicken broth; stir until it becomes a thick sauce, about 5 minutes.
Place a portion of the noodles on a plate, ladle a portion of the sauce over, and top with a small portion of the shrimp mixture. Garnish with hard-boiled eggs and green onions.