Blend 1 cup corn kernels, water, and cornmeal in a blender or food processor just until smooth.
Mix sugar, margarine, and masa harina together in a medium bowl until light and fluffy. Stir in blended corn mixture. Mix in remaining 1 cup corn, milk, baking powder, and salt until smooth.
Pour tomalito batter into the top of a double boiler over simmering water, and cover tightly with aluminum foil. Steam until firm, 50 to 60 minutes, checking water level occasionally and refilling if necessary.
Stir pudding before serving to give it a consistent texture. Serve in small scoops.
Sweet Corn Tomalito · Dinner Match Lab | Dinner Match Lab