Maou-sama ni Parfait wo Tsukuttara Yorokobaremashita

Cruz was reincarnated as a low-class demon into Makai, the underworld. In her past life, she aimed to become a top pâtissière, so now she’s bewildered by the dank food of this world! However, she is touched by the kindness of the demons around her. She declares, “I will make the citizens of Makai happy with sweets!” Cruz starts by creating the underworld's very first “parfait” with limited materials. When the demons taste her desserts, they're instantly captivated! Eventually, even the powerful Demon Lord hears the rumors of her exploits and summons Cruz to attend him…?!

(Source: Kadokawa, translated)