Slice the onion thinly. Trim the asparagus ends, peel the lower half, and cut into 2cm diagonal slices.

Heat salad oil in a pan, add breadcrumbs, and stir-fry over medium heat until golden brown. Remove and set aside as coating.

In the same pan, melt butter over low heat. Add onion and sauté over medium-low heat until softened. Add asparagus and flour, stirring until no raw flour remains. Gradually add milk and seasonings, stirring until smooth and thickened. Add clams and corn, mixing well to create the cream sauce.