I use silpat mats. I’ve tried teflon and they brown quickly with those for me. Remember if you have a new mat you need to use them several times to “season them” so as to speak.

@Fabíola Oliveira When you first buy silicone mats they are too glossy and stiff (hope that makes sense), the more you use them the more they become pliable and worn in (seasoned). So you might find that the first few times making macarons they won't turn out but after continued use they will get better. Hope that clarifies for you.

These look a bit underbaked. Try baking for a few extra minutes.

I do not know this brand but if it’s food safe then yes you can use them. I use powders and put in with my egg whites before whipping. Because the egg white is liquid it is like using in water. Powders are best used in the liquid otherwise you can get streaking if you add during macaronage stage. Hope that helps.

Beautiful

Keep trying you will get there