Clean and devein the prawns. Pat them dry with paper towels.
In a mixing bowl, combine the chili flakes, turmeric powder, and a pinch of salt. Mix until well combined. Coat the prawns in this mixture and marinate for about 10 minutes.
Heat oil in a wok or large pan over medium-high heat. Once hot, remove the prawns from the marinade, letting any excess drip off, and fry until golden brown (about 3-4 minutes). Remove and set aside on paper towels to drain excess oil.
Toss the minced garlic with the chili paste in a separate pan over low heat for about 2 minutes until fragrant. Add oyster sauce, sweet chili sauce, tomato sauce, tomatoes, green chilies, red chilies, green onions, sugar, and fish sauce. Stir well to combine.
Return the fried prawns to the pan along with any accumulated juices. Cook for an additional 3-5 minutes until everything is heated through and the sauce has thickened slightly.
Garnish with lime wedges and serve hot over steamed rice.