The character that can give you Pyro DMG and Bonus 10% DMG. Yes, I'm talking about the Chef in Wanmin Restaurant, Xiangling.
What makes her one of the best supports in the game? I will elaborate on the things that you can consider to add Xiangling to your team.
1) Pyronado - Her Elemental Burst; Pyronado can give you constant Pyro Damage especially when you want to trigger elemental damage such as Vaporize, Melt, or Overload. Here are some of the characters that will benefit her supporting powers; Childe, Beidou, Kaeya, Chongyun, Rosaria, and most of the melee characters in the game.
2) Damage Buff - After summoning Gouba, Gouba will breathe fire until Gouba leaves the field. After Gouba's duration expires it will leave a chili that will boost the current character's DMG for 10% for a short period of time.
Considering her Elemental Burst's Energy cost, getting Energy Recharge artifacts will improve the energy acquisition to replenish her elemental burst.
What are your thoughts about Xiangling?