In a small Mixing Bowl, whisk together the ¼ cup salsa de soja, ¼ cup mirin, 2 tbsp sake, and 2 tbsp azúcar morena compacta until the sugar dissolves. In a separate tiny Mixing Bowl, mix the 1 tsp maicena and 1 tbsp agua until smooth to make a slurry. Set both aside.

Pat the 1 ½ lb muslos de pollo sin hueso ni piel secados con palmaditas thoroughly dry with paper towels — this is key for a good sear. Season both sides evenly with ½ tsp sal kosher and ½ tsp sal kosher.

Heat a large Skillet over medium-high heat and add the Neutral Oil. Once the oil is shimmering, add the 1 ½ lb muslos de pollo sin hueso ni piel secados con palmaditas in a single layer, smooth side down. Do not crowd the pan — cook in batches if needed.

Sear the 1 ½ lb muslos de pollo sin hueso ni piel secados con palmaditas undisturbed for 5–6 minutes, until the bottom is deep golden brown. Flip and cook for another 4–5 minutes, until the internal temperature reaches 165°F. Transfer the 1 ½ lb muslos de pollo sin hueso ni piel secados con palmaditas to a plate and tent loosely with Aluminum Foil.

Reduce the heat to medium. Pour the ¼ cup salsa de soja mixture into the same Skillet, scraping up any browned bits from the bottom with a Wooden Spoon. Bring to a gentle simmer.

Give the 1 tsp maicena slurry a quick stir and pour it into the simmering sauce. Whisk constantly for 1–2 minutes until the sauce thickens to a glossy, syrupy glaze that coats the back of a spoon.

Return the 1 ½ lb muslos de pollo sin hueso ni piel secados con palmaditas (and any resting juices) to the Skillet. Turn the pieces to coat them thoroughly in the glaze, cooking for 1 more minute so the 1 ½ lb muslos de pollo sin hueso ni piel secados con palmaditas is heated through and well-coated.

Slice or serve the 1 ½ lb muslos de pollo sin hueso ni piel secados con palmaditas whole over steamed 2 cups arroz blanco sin cocinar, cocido al vapor según las indicaciones del paquete. Spoon any remaining sauce from the pan over the top. Garnish with sliced 2 tallos cebolletas cortadas en rodajas finas and toasted 1 tsp semillas de sésamo tostadas.