In a bowl or mason jar, thoroughly mash the banana until completely smooth—this ensures even sweetness distribution throughout the oats rather than having chunks that create inconsistent bites. Add the oats, milk, vanilla, cinnamon, sea salt, nutmeg, and flaxseed, stirring well to combine all ingredients evenly. I always use Quaker Old Fashioned oats specifically because they absorb the liquid perfectly and maintain a pleasant chewy texture overnight. Make sure there are no dry pockets of oats; they should all be incorporated into the wet mixture.

Fold in the chopped pecans and maple syrup into the oat mixture from Step 1, stirring gently to distribute them evenly throughout. I prefer Anderson's Pure Maple Syrup for its rich depth of flavor, but any quality maple syrup works well. Cover the bowl or jar and refrigerate for 4 to 8 hours, or overnight—the longer it sits, the more the oats will soften and absorb the flavors. You can prepare this in the evening and have breakfast ready to go in the morning.

Remove the overnight oats from the refrigerator and give them a good stir, adding a splash more milk if the mixture seems too thick for your preference. Serve the oats cold straight from the jar for a refreshing breakfast, or transfer to a bowl and heat in the microwave for 1-2 minutes if you prefer them warm. The pecans will have softened slightly but still provide a pleasant textural contrast to the creamy oats.