Ahi Tuna Slider with Kimchi and Cucumber

Name: Ahi Tuna Slider with Kimchi and Cucumber
Ingredients: 3 ounces fresh ahi or saku tuna, cut into long rectangles; 1 teaspoon togarashi or blackening spice; 1/2 tablespoon grapeseed oil; 1 slider roll; 1 teaspoon unsalted butter, softened; 2 teaspoons thinly sliced green onion; 4 slices cucumber; 3 to 4 fresh cilantro leaves; 1 teaspoon rice vinegar; Kosher salt and freshly ground black pepper; 3 ounces kimchi; Mint leaves, for garnish; 1 tablespoon sour cream; Large pinch of kimchi powder; Juice of 1/2 lime