The 21-year-old was introduced to the action by Darren Way just after the break and netted the Glovers’ third of the game with a towering header.
Sowunmi last featured for Yeovil back in August and the former Ipswich Town man is pleased his hard work in training has paid off.
“I’m absolutely delighted; Matty (Dolan) put it on a plate for me!” he gleefully told YTFC’s official YouTube channel.
“I was running up there on my own and I enjoyed it.
“I’ve been working hard and I’m just happy to get a goal and show the gaffer what I can.”
Yeovil have scored four goals in every home match in the Checkatrade Trophy this season.
Their latest four-goal haul sees them progress to the quarter-finals of the competition and Sowunmi already has his sights set on a trip to Wembley.
He said: “It’s about the boys’ mentality. Every game the boys put in 100% no matter who we’re playing.
“Even before today we’ve been talking about it in the changing room and that’s the goal for all of us.”
The Checkatrade Trophy quarter-final draw will be made on Thursday, January 12th at 11.30am, live on Sky Sports News.