Prepare all ingredients: wash and peel the shrimp, pat dry, dice tomatoes, slice onion, mince garlic, and grate ginger.
Heat oil in a large pan over medium heat; add sliced onion, minced garlic, and grated ginger, cooking until golden and fragrant.
Add turmeric, paprika, and chili (if using) to the pan, stirring well to coat everything in the spices.
Incorporate diced tomatoes and thyme into the pan; allow to simmer for about 10 minutes.
Gently stir in shrimp and cook until they turn pink and opaque.
Taste the stew and adjust seasoning with salt and pepper as needed.
Serve the stew hot with white rice, garnished with chopped green onions or cilantro.