The home side had to remain patient despite being in charge from the first whistle until the last, and it took something special for them to get their noses in front.
Forest goalkeeper Dean Henderson, making his competitive debut for the club after sealing a loan move from Manchester United, denied Joe Willock and Allan Saint-Maximin in quick succession, but there was nothing he could do to keep out Fabian Schar's 58th-minute missile.
He was equally helpless 12 minutes from time when Newcastle's Callum Wilson cleverly flicked Joelinton's cross past him to seal a win which might have been even more comfortable.
Howe said: "It was a brilliant performance from us, I thought, today. From start to finish, I was very very pleased.
"But at half-time, that game was still very much in the balance. Despite our dominance, we hadn't scored. Nottingham Forest had defended well and we hadn't been clinical enough in certain moments, so the main aspect of my team-talk was to make sure we didn't lose our discipline and search for that goal in a disjointed way.
"Thankfully we didn't."
Howe also admitted he was not a happy man when he saw Fabian Schar lining up his "incredible" deadlock-breaking.
Howe said: "It was an incredible strike from a player that does the unconventional, really. A centre-back shooting from that range - I probably wouldn't have reached if that was me playing.
"But he's capable of doing things like that, special moments. I was questioning his decision as he lined up to hit it, but I was delighted to see it hit the net.
"We sort of needed a goal like that to break the deadlock because we had created a number of chances and hadn't taken them, and it took a long-range goal to get us going."
The opening-day win - Newcastle did not manage a league victory until December last season - came just 24 hours after head coach Howe had committed his future to the club by signing a new long-term contract.
He said: "I didn't hesitate about signing it. I'm loving every moment of being Newcastle manager and I'm going to give it my all to try to make it a success."