Toast pecan halves in a dry skillet over medium heat until fragrant and golden.
Let toasted pecans cool completely, then set aside two tablespoons for garnish.
Add vanilla ice cream, whole milk, and maple syrup to a high-speed blender.
Blend base ingredients on medium speed until smooth and completely combined throughout.
Add remaining pecans, vanilla extract, and sea salt to the blender mixture.
Blend on high speed until pecans are finely chopped but still textured.
Check milkshake consistency and adjust with additional milk or ice cream as needed.
Pour maple pecan milkshake into chilled tall glasses for the best temperature and presentation.
Top generously with fresh whipped cream and reserved toasted pecans for decoration.
Drizzle extra maple syrup over the top and serve immediately while cold.