A wingover also known as a 'return to target' manouevre is the quickest way to do a 180 whilst still maintaining significant fwd speed.
Whilst in fwd speed (suggest >80-100+kts) initiate a pull up to around 20 ish nose up, let the speed slide back to a min of around 60+ kts, roll right or left 30+ AOB [The more you roll the more exciting it feels/looks]. Roll out 180 degrees from inbound heading and return to level flight at the height you entered. Balance in turn.
There is a 'tighter' manouevre called a torque turn but thats lesson 2!