Preheat oven to 325 degrees F.
Spread the pecans on a cookie sheet, and place in the oven for 3 minutes. For even toasting, turn the tray, front to back. Toss the nuts with a metal spatula and bake for another 3 minutes. You'll know they're done when they give off their fragrant aroma, and be sure to check them so they don't become overbaked or charred.
Line a cookie sheet with baking parchment.
Fit a heavy-bottomed saucepan with a candy thermometer. Over high heat, cook the cream, butter, and brown sugar to 240 degrees F (soft ball). If necessary, stir once to help dissolve the sugar. Remove from the heat and let sit for 15 seconds.
Carefully (it may sputter) stir in the vanilla, bourbon, and toasted pecans. Vigorously stir with a spoon for 10 seconds, until the mixture looks creamy and slightly thickened. Drop by tablespoonfuls onto the prepared cookie sheet.
Let cool for 20 minutes.