Oats
When the day starts off right, it may be because you had oats at breakfast.
Oats are a super-versatile herbaceous plant. You can eat them in grains, flakes, as flour, in sweet or savoury dishes and to make porridge (try it with fresh fruit or almonds and hazelnuts). They contain a lot of fibre and are well tolerated by the gluten intolerant (but must be from a controlled supply chain), and we love them. Above all because we humans have finally changed our minds about them, having for decades just given them to horses to eat.