1. Gather all ingredients: dark brown sugar, granulated sugar, salt, heavy cream, vanilla bean, maple syrup, dark rum (optional), coarsely chopped or halved walnuts, and unsalted butter.
2. In a saucepan, combine dark brown sugar, granulated sugar, salt, heavy cream, vanilla bean seeds, and maple syrup. Add dark rum, if desired.
3. Whisk the mixture until it is fully blended and free from lumps.
4. Heat the saucepan on medium heat and stir constantly as the mixture comes to a boil.
5. Reduce the heat to medium-low and continue stirring until the sugar is completely dissolved and the mixture becomes smooth and bubbly.
6. Stir in the walnuts and unsalted butter, ensuring the butter melts completely into the mixture.
7. Simmer the walnut mixture for an additional 5 minutes while stirring occasionally.
8. Remove the saucepan from the heat and let the mixture cool slightly for 12 to 15 minutes.
9. Prepare a baking sheet lined with parchment paper.
10. Use a spoon or scoop to drop spoonfuls of the praline mixture onto the parchment paper. Work quickly, as the mixture begins to set.
11. Allow the pralines to cool at room temperature for at least 30 minutes until they are fully set.
12. Once the pralines are firm and cool, transfer them carefully to an airtight container.
13. If stacking pralines, use wax paper between each layer to prevent sticking.
14. Store the pralines in a cool, dry place for up to one week. Alternatively, refrigerate for up to two weeks or freeze for up to three months for long-term storage.
15. Optionally, customize with variations such as adding chocolate, spices like cinnamon, or trying different nuts such as pecans or cashews.
16. Enjoy your Maple Walnut Pralines as a standalone treat, gift, or topping for desserts like ice cream, parfaits, or cakes!