Crush seeds with mortar and pestle. Scrape the seeds into a small bowl. Add the remaining sesame sauce ingredients; mix well.
Heat wok or large cast iron skillet over medium high heat. Add vegetable oil and ginger. Saute until fragrant and discard the ginger. Add the beef and stir fry for few minutes or until lightly brown. Add the vegetables and the sesame sauce. Cook for 2 to 3 minutes. In a small bowl, combine 1 tablespoon water and the cornstarch. Stir until dissolved. Add it to the beef and stir to thickened. Garnish with toasted sesame and green onions.
Recipe by The Gluten Free at https://www.theglutenfree.com/gluten-free-mongolian-beef-2/