- Combine the milk, butter and vanilla in a medium pot over medium. Bring to a simmer.Combine dry ingredients in a mixing bowl.
- Pour the eggs (lightly beaten) and warm milk mixture into the flour mixture and whisk gently and as little as possible, just to combine.
- Add the rum and stir very gently, just to combine.
- Cover the bowl with plastic wrap and leave on the counter, out of direct sunlight, for 2 hours.
- Preheat the oven to 400 degrees F. Butter or spray with cooking spray 18 canelés molds, mini-muffin molds or tartlet molds.
- Pour the batter into the prepared molds, making sure to fill no further than half-way up.
- Bake 35-40 minutes, or until the tops are very brown, almost burned at the edges.
- Unmold canelés and let cool completely before serving.