Crème brûlée is mostly custard that has been topped with caramel.
Paleo and Sugar
Sugar is not strictly Paleo, but when consumed in moderation, there’s no reason not to include it as part of the 20% of the 80/20 rule. If you can tolerate dairy and that crème brûlée on the menu is just calling your name, go for it. It will serve as a welcome indulgence that is unlikely to wreak havoc on your body, so long as the rest of your meal is full of meat and veggies.
Homemade Is Always Better
If you want to try to make your own, you can absolutely do so and make it completely Paleo by using coconut milk instead of dairy.