Heat oil in a saucepan over medium heat. Add onion and cook until wilted, about 3 minutes. Add peas and kohlrabi; stir to combine. Add dill and seasoning blend; stir to combine.
Add water to cover vegetables and bring to a boil. Reduce heat and cover halfway with a lid. Cook until peas and kohlrabi are soft, about 20 minutes more. Cool to room temperature before serving.
