Line a large baking sheet with parchment paper; set aside.
In a medium saucepan stir together the sugars, heavy whipping cream, and the baking soda.
Over medium heat bring to a boil stirring occasionally. Allow to boil until a temperature of 235 F is reached. Remove from the heat immediately. Stir in the butter and the vanilla. Quickly add the pecans and vigorously stir for about 1 minute.
Working quickly, drop by heaping tablespoonfuls onto the prepared cookie sheet.
Allow to cool until set.
Notes
Adapted from Taste of the South: Pecan Everything special edition 2018