Pat the shrimp dry with paper towels, ensuring they are free of excess moisture for a good sear.
In a small bowl, mix together paprika, cayenne pepper, garlic powder, onion powder, thyme, and oregano to create your homemade Cajun spice blend.
Heat the skillet over medium-high heat until hot, then add the oil and let it shimmer, filling the kitchen with a faint sizzle and aroma.
Add the sliced bell peppers to the skillet and sauté for about 2-3 minutes until slightly softened and fragrant, stirring occasionally.
Push the peppers to one side of the pan, then place the shrimp in a single layer on the empty side, sprinkling generously with the spice mix.
Sear the shrimp for 2-3 minutes without moving, until they develop a pink hue and a slight char on the edges, releasing a smoky aroma.
Flip the shrimp using tongs, sprinkle more spice if desired, and cook for another 2-3 minutes until fully pink and opaque, with the peppers tender and caramelized.
Squeeze fresh lemon juice over the skillet contents and toss gently to coat everything evenly, allowing the flavors to meld for a minute.
Remove the skillet from heat and transfer the Cajun shrimp to a serving plate. Garnish with chopped green onions or parsley for a fresh pop of color and flavor.
Serve immediately, enjoying the tender shrimp coated in smoky, spicy flavors with the bright citrus and fresh herbs.