Preheat oven to 400ºF. Prepare a muffin tin by lining with paper or silicone liners, or by spraying the compartments well with cooking spray.
Combine in a bowl the flour, ground oatmeal, flax seed meal, baking powder, and salt. Set aside.
In a large bowl, whisk together the jam, sugar, eggs, oil, milk, and vanilla. Add the dry ingredients to the wet, and stir together until just combined.
Divide the batter equally into the prepared pan, filling each cup about 2/3 full.
Bake for 18-20 minutes, or until a toothpick or wooden skewer inserted into the center of the muffins comes out clean.
Notes
To make ground oatmeal, measure ½ cup of uncooked oatmeal (old-fashioned or quick oats, but not instant), and grind in a food processor until fine.