I love sauces. I have a small collection that takes up far too much space in our fridge. Now when I say 'collection' I am not actually kidding.
List of sauces currently in my flat:
Sweet n Sour Sauce
Sweet Thai Chili Sauce
Bourbon BBQ Sauce
Piri Piri Mayonnaise
Sweet Chili and Ginger Relish
French Dressing (American style)
and various gravys can be whipped up at a moment's notice
Sometimes when you're a picky eater like myself, you end up eating the same thing over and over and over again in order to avoid aversive tastes. Especially if you are unable to spend time cooking a grand dinner. Sometimes it IS better to just stick with what you know, especially if you have one food you like that is actually healthy for you. Sauces are one of the best ways of changing things up. My love affair with sauces started after sampling the array of british and indian sauces at my boyfriend's parent's house while eating chip shop chips.
But let us take lean chicken breast as an example. I have invented many different ways of jazzing this up. One of my favorites is by making Orange Chicken. I'm also a fan of Sweet n Sour Lime Chicken.
It may also be useful to peruse the sauce isle(s) of your own supermarket and try something new.
If you're in America, I'm aware that many large supermarkets offer a huge array of BBQ sauces and chinese/japanese cooking sauces. YUM.