Preheat oven to 425 degrees.
Arrange the cod pieces in the bottom of a covered baking dish.
Tuck the broccolette around the cod.
Top each piece of cod with lemon slices and scallions. Drizzle with toasted sesame oil, a dash of flaky sea salt and freshly ground pepper.
Cover and bake for 15 minutes.
Uncover and bake for 5 - 7 minutes, or until cod is just beginning to flake and the broccolette are al dente.
Broccolette is also known as broccolini.