Pat salmon cubes completely dry with paper towels to ensure a crispy sear.
In a mixing bowl, toss the salmon with garlic powder, salt, and black pepper until evenly coated.
Heat olive oil in a large skillet over medium-high heat until shimmering.
Add salmon cubes in a single layer, searing for 2 to 3 minutes per side until a golden-brown crust forms and the internal temperature reaches 145°F (63°C).
While salmon cooks, whisk together mayonnaise, sriracha, soy sauce, and honey in a small bowl.
Partition cooked rice into two serving bowls.
Arrange the crispy salmon, cucumber, avocado, and edamame over the rice base.
Drizzle the spicy mayo dressing over the bowls.
Garnish with toasted sesame seeds and sliced green onions before serving.