Blend the oat grains coarsely in a food processor or blender (if oats are not already steel-cut).
Toast the oats in a pan without oil for a minute (optional, you can toast the oats even before blending it if you prefer).
In a glass bowl or jar, add the steel cut oats, vegetable milk and water. Add lime or lemon juice, zest, salt and maple syrup. (You can also add these ingredients later).
Stir and put in the combi-steam oven. Steam the porridge for 30 minutes.
In a second glass or bowl, add the blueberries with a tablespoon of water or lime / lemon juice.
Put the blueberries in the combi-steam oven and continue steaming the oats and blueberries for another 30 minutes. (NO microwave or oven function. Steam at maximum power without lid - see photo). You can cook the porridge for only 30 minutes and then immediately close the jar with a lid, leaving it in the steam oven turned off.
The following morning (or after 6-8 hours), add to the porridge 2-3 tablespoons of vegetable milk if necessary, almond butter, the chosen flavors and syrup. Heat the porridge and the blueberries separately for 10 minutes in the steamer (while you prepare the coffee and take a shower!). Alternatively, transfer to a saucepan and heat 2-3 minutes on the stove, stirring.
Take away: if you decide to bring porridge to work, pour the blueberry sauce over the porridge, close the jar and take it with you. Heat the porridge before serving.
If you do not have a combi steam oven: make the steel cut oats by following steps 1 and 2. Continue as indicated in this video recipe. You will have to increase the cooking time. The steel-cut oat takes about 35-40 minutes to cook on the stove.