Put all the ingredients in a medium saucepan. Heat over medium heat, stirring constantly with a wooden spoon, until everything is melted, incorporated, and reaches softball stage on a candy thermometer (20-25 minutes). Make sure you stir around the inner edges of the pot too or you will get dark brown flecks in your candy.
Turn off heat and continue to stir until it begins to thicken, around 175-200 degrees on a candy thermometer, and looses its gloss. This step will take about 15-20 minutes so be patient and don’t stop stirring.
Add the vanilla and pecans, stirring to incorporate.
Drop by the spoon full onto waxed paper. (Be sure you have this laid out ahead of time. Once the pralines are ready to spoon out they don’t take long to get too cool and will turn grainy! Be quick!)