Season the shrimp with salt. Heat olive oil in a large skillet over medium-high heat. Add shrimp in a single layer; sear for 2-3 minutes on each side until pink and browned. Remove shrimp and set aside.

In the same skillet, lower heat to medium and add butter. Once melted, toss in diced onion and minced garlic. Sauté for 2-3 minutes until onion is translucent and garlic is fragrant.

Stir in tomato paste. Cook for about 7 minutes, until it darkens slightly. Add peri-peri spice mix in the last 2 minutes.

Pour in white wine, stirring to deglaze the pan. Simmer for 3 minutes, then add chicken broth and let reduce for about 5 minutes until sauce thickens.

Return the shrimp to the skillet. Cook for another 3 minutes until shrimp are done. Stir in chopped cilantro before serving.

Serve the shrimp hot over rice or with crusty bread.