While the crust is baking, combine eggs, Karo Syrup, sugar, melted butter and vanilla in a large bowl. Mix well. Stir in pecans. Pour over the crust, spread evenly, and return to oven to bake for 25-30 minutes longer until firm around the edges and center starts to firm up as well. Allow to cool completely before lifting the foil liner out of the pan and cutting into bars.