Preheat the oven to 375 degrees F, and line or grease muffins tins for 18 large or 24 medium muffins.
In a small bowl, mix the oats with the boiling water, and set aside to cool slightly.
In a large bowl, lightly beat the eggs, and then stir in the yogurt, milk, molasses, and oil. Add the oat/water mixture and combine thoroughly.
In a separate large bowl, whisk together the oat bran, whole wheat or gluten-free flour, brown sugar, baking soda, cinnamon, and salt. Add this mixture to the wet ingredients, and then stir in the raisins. Mix until just combined.
Transfer the batter to the prepared muffins tins. (I like to use a large ice cream scoop with a release for easy transfer and evenly-sized muffins.) If desired, sprinkle the tops of the muffins with a pinch or two of dry oats. Bake for 15-18 minutes, depending on size of muffins. When done, the muffins will be dark brown and a toothpick inserted in the middle should come out clean. (To ensure perfectly cooked muffins, check a little early and and extend cooking time, if needed, as all ovens vary a little.)
To preserve freshness, I refrigerate the muffins in an airtight container, although they may sit for a couple of days, covered, at room temperature. These muffins freeze well, too.