Blend well together the oats, pecans and half of the sugar with the melted butter. Divide the mixture into 10 x 6cm foil dishes. Push the crumble to coat sides and bottom of the dishes. Bake in a hot oven, temp 180 for 10 minutes. Take off the heat, reduce oven temp to 175`c. Meanwhile beat the cream cheese with the vanilla & remaining sugar until light and fluffy. Stir in the Greek yogurt. Divide the mixture between the oats cases, bake for approximately 20 minutes. Meanwhile, prepare the sauce. Cook the sugar and syrup over a moderate heat, simmering for about 5 minutes. Remove from heat, stir in the butter, carefully adding the evaporated milk and vanilla essence, stirring continuously. Spoon the sauce over the cheese cakes, garnish with a few sea salt flakes and extra pecan nuts.