Rodel Richards opened the scoring for the hosts on 20 minutes before two spot-kicks in the second half changed the game.
On 55 minutes, Morgan Boyes was sent off and Jamie Bowden made no mistake from the spot, then five minutes later the same player converted another penalty to make it 3-0.
Spurs added a fourth goal in stoppage-time as Bowden claimed his hat-trick, and the home team also ended up with 10 men when Malachi Fagan-Walcott was shown a red card.
Reflecting on the game, U23s boss Neil Critchley told Liverpoolfc.com: “I thought the first half was even but they had the better of the first 20 minutes, then we were the dominant team right up until half-time and missed a good opportunity to equalise.