Crust

A Water Code Burst 2 Rocket Launcher support who can split allied Attack Damage plus distributed damage or sustained damage increases to fit your battle plan.
Maillard and Blanching do not stay active together, so decide early in the battle which one to use and lock the state in with your normal/Full Charge pattern.
Reliable Cooking2 adds DEF support and debuff cleansing, and her Burst cooldown is 20 seconds.

Grill and Boil1: when a Full Charge attack fires, it extends Maillard duration for all allies if Maillard is active, or Blanching duration if Blanching is active. Landing three non-Full Charge normal attacks applies Maillard to all allies, granting Increased ATK based on the caster's ATK and removing Blanching. Holding Full Charge for 1 second or more three times applies Blanching to all allies, granting Increased ATK based on the caster's ATK and removing Maillard.

Reliable Cooking2: after three non-Full Charge normal attacks, or three actions of holding Full Charge for 1 second or more, it grants Increased DEF to all allies not under Reliable Cooking2 and cleanses one debuff. If Maillard or Blanching is active when Full Burst Time begins, it grants all allies additional Increased ATK based on the caster's ATK.

True FlavorB grants all allies an Attack Damage increase. Under Maillard it also grants all allies a distributed damage increase, and under Blanching a sustained damage increase.

If the lineup boosts distributed damage, build Maillard with mostly normal attacks at the start of battle. If it boosts sustained damage, complete three actions of holding Full Charge for 1 second or more to build Blanching.
Reliable Cooking2 rotates the DEF buff and cleanse the same way. If you need the cleanse urgently, alternate normal and Full Charge patterns.
Use True FlavorB after entering Full Burst while Maillard or Blanching is active.

The two show up in the same squad in distributed damage-focused lineups.

If Rocket Launcher reload is long, prioritize Reload Speed. Use the Bastion Cube to support ammo refill. In squads with fast Burst rotation, a cube that fills Burst Gauge is the runner-up. If Harmony Cube levels differ a lot, use the higher-level cube ahead of the ranking.

Set Elemental Advantage damage and ATK as the baseline. For Rocket Launcher play, adjust Full Charge frequency with ammo and Charge Speed.

True FlavorB packs the team ATK buff and the branching buff together, so level the Burst first. Grill and Boil1 carries most of the Maillard/Blanching upkeep and extension, so raise S2 next. Reliable Cooking2 is DEF/cleanse support, so fill it in with leftover materials.

Her role is clear in boss fights against Fire Code enemies (= Water advantage) and in distributed damage/sustained damage lineups. In Campaign and Tribe Tower she is worth slotting when you need buffs and cleansing. Her Arena priority is fairly low.

A single Burst grants an Attack Damage increase plus either a distributed damage or sustained damage increase, depending on Maillard or Blanching.
Reliable Cooking2 applies Increased DEF and cleanses a debuff at the same time.
With a 20-second Burst cooldown, she is easy to rotate in the Burst 2 slot.

Maillard and Blanching cannot be active at the same time, so you have to commit to whichever one suits your team.
Alternating between distributed damage and sustained damage increases within one round is difficult.
As a Rocket Launcher, she builds her states slowly unless reload and Charge patterns are aligned.