This is a test of commonsense. Complete the next sentence:

How to make a bouillabaisse
Prepare all your ingredients and utensils.
Make sure the fish you use is at room temperature, and has been for at least 20 minutes, so they don't slow down the speed at which the stew boils. Laying out all of your ingredients and utensils before you start making the bouillabaisse allows for better organization and more efficient preparation.
Pour the olive oil into one of the cooking pots and heat it over medium heat. Add the chopped onion and leek until they're soft and slightly translucent.