Whisking savory miso and creamy mayonnaise together creates a flavorful condiment you’ll use a few ways in this speedy sheet-pan dinner. First, with a bit of soy sauce mixed in, it acts as a coating for boneless chicken thighs, helping to both season the meat and promote caramelization as the chicken cooks. Then, with a splash of rice vinegar for brightness, the miso-mayo spread becomes a finisher you can drizzle on your hearty rice bowl, bulked up with tender roasted brussels sprouts and leeks.