Hamilton's advantage was such that he finished over 20 seconds clear of Mercedes team-mate Valtteri Bottas to triumph at the event for the second year in a row.
Hamilton said: "The vehicle and myself, I felt that synergy that I hadn't been feeling all year". I was feeling good. This 64th career victory is his third in Barcelona.
"I remember like it was yesterday sitting at home playing this computer game as Michael", Hamilton said. "We let him down in Melbourne and that stays in your mind and now he has put these things behind him and had a very good weekend". He has some serious records. Sixth was Haas driver Kevin Magnussen, who helped convert the team's strong pace into a healthy haul of points. "This weekend, we got ourselves on the right path".
After the early safety vehicle for a multi-car crash caused by Haas driver Romain Grosjean in Turn Three, Hamilton bolted at the re-start and had a 1.4-second lead at the end of the first racing lap.
Hamilton had also won in Azerbaijan two weeks ago, but that victory came mostly because of incidents involving his closest competitors, including a blown tire for Bottas and a crash between Red Bull teammates Daniel Ricciardo and Verstappen.
Bottas, meanwhile, had to regain P2 after losing out to Scuderia Ferrari's Sebastian Vettel on the start, with Vettel getting ahead and into second.
But Vettel struggled with tire wear and Ferrari chose to bring him in for an extra stop. When asked why Raikkonen was one-stopping and he was two-stopping, Vettel said it was down to the timing of the first pit stop.
"For us it was not an option to stay out", Vettel said. "I don't think it's only the track", he said.
After Lewis Hamilton and Valtteri Bottas locked out the front row, with Hamilton scoring the pole, the two rolled to a 1-2 for Mercedes on race day, as the team returned to its dominant self after a somewhat slow start to the 2018 season. Vettel won in Australia and Bahrain, while Ricciardo was first in China and Hamilton triumphed in Azerbaijan.
Hamilton led from pole, with Vettel nipping forward of Bottas to take second, however behind them there was carnage as Romain Grosjean span his Haas, with the luckless Nico Hulkenberg (Renault) and Pierre Gasly (Toro Rosso) ploughing into him. He had a spin shortly after the Ocon-induced virtual safety vehicle.
"For us it was a flawless result today", he added. "I had no idea how the race was going to play out. The more comfortable I am, the more the pace shows".
"Feels nice to be on the podium and nice to have a good clean race", said Verstappen.
To finish a sorry afternoon for Ferrari, his teammate Kimi Raikkonen was pressured to retire, leaving Mercedes to take the lead within the constructors' championship with a 27-point benefit.