Pies, doughnuts, cheesecakes, cakes, tarts and ice cream are often drizzled or covered with sweet sauces. Whether you are making your dessert sauce from scratch, or buying it already made, you may want to thicken your dessert sauce so that it is less runny and has a heartier consistency. By taking a few moments in the kitchen to prepare, you can get your dessert sauce to the thickness you desire without too much effort.
Place your thawed raspberries, powdered sugar and lemon juice into a blender. Puree the contents until they are smooth and the frozen chunks are absorbed.
Strain your raspberry mixture from the blender into a bowl. Keep the seeds and other fruit flesh out of the bowl.
Evaluate the consistency of your raspberry coulis with a whisk. If it appears to be too runny, thicken the sauce by whisking in more powdered sugar. Add a little bit of powdered sugar - one tablespoon at a time. After each tablespoon that you add, whisk the mixture up and evaluate the new consistency until you come to a thickness that you like.
Combine the water and sugar in the medium saucepan over low heat. Cook five to 10 minutes so the sugar dissolves.
Increase the heat and allow the mixture to boil and bubble for about five to seven minutes. The sugar water will now turn a brown color as it caramelizes. Turn the heat back to low once the mixture reaches the desirable color, so that you do not risk burning the caramel.
Slowly add the cream and vanilla extract to the caramel sauce in the pan. Mix it up.
Add 1 tsp. of cornstarch to your caramel sauce at a time, whisking it each time you add some. Cornstarch is a thickening agent that will make your caramel sauce firmer and stickier. Continue adding the cornstarch until you reach a thickness you like. Also, keep in mind that as the caramel sauce cools, it will thicken a little. So you do not want to add too much cornstarch to the pot, or else it could make your sauce too thick and stiff.