I recently encountered a few recipes where food is not allowed to 'get colour', or become brownish while baking. A few examples of what I mean: Chicken turns a golden-brown colour. Burgers get a very dark crust. Unions turn brown.

How do I avoid my food becoming this colour when baking, while still cooking them? Is there a way that works in general or if not, a way to find out how to do this for the food I am cooking today?

For example, in this recipe for white asparagus panna cotta, the brownish colour is undesired.

Bak de asperges een minuutje of 5; ze mogen niet kleuren! - Bake the asparagus for about 5 minutes; don't let them change colour (translation mine)