After the young international set the Hammers on their way, centre-half Manny Onariase rose highest to head home Matt Carter's corner and put the Hammers 2-0 ahead after just 15 minutes, before Hector-Ingram grabbed his second and West Ham's third before the break.
With the result seemingly already in the bag, the Hammers refused to let their north London opposition into the fixture and added a fourth through Jordan Brown's strike, with the game then put to bed when Vashon Neufville fired in his first goal of the season to end a five-star performance from the visitors.
The Hammers were again coached by Mark Phillips, who made four changes to the starting XI that beat Brighton & Hove Albion at Little Heath a week earlier. Noha Sylvestre, Kieran Bailey, Jake Eggleton and Anthony Scully were replaced by Alex Pike, Neufville, Grady Diangana and Brown (pictured), who all missed out against Brighton due to Development Squad commitments.
It took the visitors just seven minutes to open the scoring against Arsenal when midfielder Joe Powell broke down the left with speed and put an early cross into the danger area, which was finished well by Hector-Ingram for his third goal of the season.
On 15 minutes, the Hammers doubled their lead when Onariase timed his run perfectly to meet Carter's corner with a bullet header that gave Arsenal keeper Hugo Keto no chance of saving.
From that position onwards, West Ham controlled the remainder of the half and even managed to add a third before the break when Hector-Ingram used his strength to hold off a defender and chip the ball over Keto for his second goal of the game.
After the break, Arsenal stepped up their performance level in an attempt to try and get back into the game. However, the young talent on show for the Hammers kept the Gunners quiet for the remainder of the game.
West Ham added their fourth when Brown buried the ball into the back of the net from Jerry Amoo's cutback, before Neufville fired in from 18 yards to extend the Hammers lead to 5-0.
Phillips was delighted with the convincing win over Arsenal and revealed that a change in formation perhaps shocked the Hammers' opponents.
"It's a fantastic result for us as there aren't many teams that go away to Arsenal at any level and get a result like we did," said Phillips. "I changed the formation a little as I thought Arsenal would be expecting us to match them with three in the middle of the pitch but we switched to 4-4-2 and I think we caught them out.
"Overall, I'm very happy with the performance and can't really pick anyone out that didn't put in a good performance.
"We have Fulham at home next week and we go into that off the back of two victories so we will prepare as usual for that game and look forward to hopefully getting another result next weekend."
Also on Saturday, 16-year-old defender Reece Oxford was an unused substitute for Sam Allardyce's first team at Liverpool. After coaching him regularly over the past few years, a proud Phillips admitted that experiences like this will really aid Oxford's development over the next few years.
"I think I know Reece just as much as anyone else at this Club after coaching him from as young as U13s and I think that a player of his ability and character deserves opportunities like this," confirmed Phillips. "It gives him a chance to get involved with the first-team squad and see how they go about their business on a match day.
"I'm pleased that Sam Allardyce has given Reece this opportunity and I know that as a very level-headed person, it will help bring the best out of him in the future."
The Hammers' next Barclays U18 Premier League South fixture is at home to Fulham on Saturday 7 February, with kick off at 11am. Parking and admission are both free at Little Heath.
U18s: Howes, Pike, Onariase, Akinola, Neufville, Carter, Diangana (Bailey), Powell (Borg), Amoo, Brown (Scully), Hector-Ingram
Subs not used: Bogard, Sheriff