Here is the recipe I use when I want hollandaise. The real stuff doesn't last long enough and is too fussy to make.
Mock Hollandaise Sauce
1/4 cup sour cream
1/4 cup real mayonnaise
1 teaspoon lemon juice
1/2 teaspoon prepared mustard
Blend the ingredients, cook and stir until hot
Real Hollandaise sauce separates after about 90 minutes. This recipe tastes similar and keeps in your refrigerator for weeks. Tastes great on vegetables. Sometimes I add curry or cayenne pepper to taste as a variation