1 can whole peeled tomatoes drained with juice reserved
1/4 cup pitted brine-cured green or black olives chopped coarse
2 tbsp coarsely chopped fresh parsley
2 scallions sliced thin on bias
Toss shrimp with 1 tablespoon oil, 1 teaspoon garlic, lemon zest, 1/4 teaspoon salt, and pepper; refrigerate until ready to use.
Using highest Sauté function, heat remaining 1 tablespoon oil in Instant Pot until shimmering. Add bell pepper, onion, and remaining 1/4 teaspoon salt and cook until vegetables are softened, about 5 minutes. Stir in remaining garlic, ras el hanout, and ginger and cook until fragrant, about 30 seconds. Stir in tomatoes and reserved juice.
Lock lid in place and close pressure release valve. Select Pressure Cook function and cook for 15 minutes. Turn off Instant Pot and quick-release pressure. Carefully remove lid, allowing steam to escape away from you.
Stir shrimp into tomato mixture, cover, and let sit until opaque throughout, 5 to 7 minutes. Stir in olives and parsley and season with salt and pepper to taste. Sprinkle individual portions with scallions and drizzle with extra oil before serving.