In a small saucepan, mix the cream, butter, salt and vanilla. Heat over medium heat until butter is melted.
In the meantime, in a large saucepan, mix together sugar, corn syrup and water. Put a candy thermometer on the side of the saucepan and bring to a boil over medium-high heat until sugar turns caramel. Do not stir the sugar, gently stir the pan as needed to evenly heat the sugar and stir.
Once the sugar has turned a caramel colour, slowly stir in the hot cream, being careful not to add it too quickly as the mixture may overflow.
Continue to boil until the caramel reaches 248 degrees on the candy thermometer about 8 minutes.
Spread the caramel evenly over the oat crust and garnish with chopped pecans.
Let cool for 30 minutes.