Heat 2 tablespoons olive oil in a large saucepan or Dutch oven over medium heat. Add the chopped onion and minced garlic, then cook for about 5 minutes, stirring occasionally, until the vegetables are soft and fragrant.

Stir the curry powder, 1 teaspoon ground cumin, and cayenne pepper or crushed red pepper into the softened onion mixture. Cook for about 1 minute, stirring constantly, until the spices smell fragrant.

Add the whole peeled tomatoes and chicken stock or low-sodium chicken broth. Bring the mixture to a boil, reduce the heat, and simmer for approximately 15 to 20 minutes.

Purée the soup until smooth with an immersion blender, or blend it in small batches using a standard blender. Season with kosher salt and freshly ground black pepper, then return the soup to the pan and keep it warm.

Heat the oven to approximately 425°F. Toss the peeled and deveined shrimp with 1 tablespoon olive oil, 1 teaspoon ground cumin, salt, and pepper, then arrange them in a single layer on a baking sheet.

Roast the shrimp for about 5 to 7 minutes, turning once if needed, until they are pink and opaque. Remove them as soon as they curl slightly because residual heat will continue cooking them.

Ladle the hot soup into bowls and top each serving with the cumin-roasted shrimp. Garnish with chopped fresh cilantro if desired and serve immediately.