whats the best ab-toning workout?

like a DVD or something. i want something that takes less than 15 minutes a day. probably 10 min or something, with quick results and isnt super hard. i know this is like the dream workout, but if its out ther i want to find it! please write what workouts you’ve done that you’ve gotten good and quick results,
thanks!
also, i dont want to have to buy weights or like a ball or anything. i have an ab-lounge, but other than that i want to do it with just me.