Preheat oven to 425 degrees F. Line a sheet pan with aluminum foil, brush with oil or spray with cooking spray.Trim off any rough ends of broccolini. Leave any leaves still attached.On the baking sheet or in a large bowl, toss broccolini with olive oil and soy sauce. Spread onto baking sheet in a single layer (overcrowded or overlapping vegetables won’t get as crispy).Bake for about 15 minutes or until broccolini is tender and tips are golden brown and crisp.Remove from oven; serve while still warm and crispy, sprinkled with flake sea salt to taste.