Rinse jasmine rice in cold water until the effluent is clear.
Combine rice and 1.5 cups water in a saucepan; bring to a boil, then reduce heat to low and simmer covered for 15 minutes.
Remove rice from heat and let stand covered for 5 minutes before fluffing with a fork.
Pat shrimp dry with paper towels to ensure optimal Maillard reaction.
Season shrimp uniformly with garlic powder, smoked paprika, salt, and black pepper.
Heat olive oil in a stainless steel or cast iron skillet over medium-high heat until shimmering.
Sear shrimp for 120-180 seconds per side until an internal temperature of 145 degrees Fahrenheit (63 degrees Celsius) is reached.
In a small mixing bowl, whisk mayonnaise, sriracha, and lime juice until a homogenous emulsion is formed.
Apportion the cooked rice into two bowls.
Arrange the seared shrimp, cucumber, and avocado slices atop the rice bed.
Apply the spicy mayo dressing via drizzle and garnish with sesame seeds and green onions.