When to use en and de?

Question

I've always found it confusing to use both of them like in this phrase is it les œufs en chocolats or les œufs de chocolats?

Maarten Kamp · Accepted Answer

The link in your question seems to have nothing to do with the question itself. Can you link the exercises here that you are querying ? 
The link below is to the lesson here :  
https://progress.lawlessfrench.com/my-languages/french/view/207

Céline Pickard · Answer

Bonjour Autumn Rain,
In French, you will say "les œufs en/au chocolat" as they are made of / made with chocolate. You could use de but it is not the best/most used option at all in this particular instance.
Take a look here for more details: /revision/grammar/compound-nouns-are-formed-using-prepositions-a-de-en
I hope this is helpful.
Bonne journée !