Not many people have tried the Tim Hortons French Vanilla, but I will tell you it is one of the best drinks they have. I recently tried making it at home, and it turned out way better than I thought it would. Sure, you can easily buy their French vanilla mix for under $10, but it's way tastier to make it from scratch.
Combine instant coffee granules and hot chocolate mix with ¼ cup of boiling water in a cup. Stir until dissolved.
Add warm milk and vanilla, and enjoy! You can pop the cup in the microwave for 30 seconds if you want it hotter.
Optional: If you want a frothed milk look, heat some milk to around 160°F; it should be hot but not scalding. Then, pour it into a small jar or glass container and shake it vigorously to create a lot of bubbles. Spoon on top of coffee.
Notes
Hot chocolate powder: You can make homemade hot chocolate powder by combining ½ teaspoon of cocoa powder, 1 teaspoon milk powder, and 1 teaspoon of powdered sugar.