How do You Make Kahlua?

My homemade recipe goes like this: Put 2 cups of water to boil; add 4 cups of sugar and let simmer for 15 minutes. Dissolve 10 level teaspoons of instant coffee in 1 cup of hot water and add to sugared water. Pour all into a large jug, add 1 teaspoon vanilla, 2 teaspoons glycerine and 1 quart of vodka. Pour in bottle, cap, shake and let sit for 2 weeks. Yes!