Pour cream into a heavy saucepan, and swirl up all sides. Add sugar, butter, cream of tartar, and salt, and stirring constantly, bring to a boil over medium-high heat. Stir in corn syrup. Then wash down sides of pan and the spoon.

Cook, stirring occasionally until it reaches 240 °F.

Remove from heat, and pour directly onto marble slab (do NOT scrape the sides of the pan). Allow to cool enough to touch and handle, and add vanilla. Beat and knead with a bench knife, wooden spoon, or your hands until it loses its shine, and becomes the texture of smooth fudge. Immediately form into rolls measuring approximately 5 inches long by ¾ inch diameter, and wrap tightly with plastic. This recipe makes approximately 10 rolls of that size. Refrigerate for up to a week or freeze for 3 months.

Line an 18x13-inch baking sheet with sides with parchment, and set aside.

Melt butter over low heat in a 3-quart saucepan. Add sugar, cream, corn syrup, and salt. Bring to a boil and cook until it reaches 238-240 °F (soft-ball stage).

Remove from heat, and stir in vanilla. Pour caramel into the parchment-lined baking sheet, and spread to edges. Allow to cool completely.

Using a pizza cutter (or sharp knife), cut the sheet of caramel into 10 (6x3-inch) rectangles.

Place one log of fondant in the center of each caramel rectangle, and wrap the caramel all the way around it, sealing in all edges.

Roll each caramel wrapped log in chopped pecans.

Wrap tightly in plastic, and refrigerate for at least two hours.

When ready to eat, slice and serve.