Sutton, who rejoined Motherwell in the summer following two years with Hearts, headed home substitute Lionel Ainsworth's corner to level in the 54th minute and finished emphatically midway through the half after latching on to Henri Anier's ball over the top.
Bob McHugh's bullet header rounded off Motherwell's fifth win in six games and McCall's decision to bring Sutton back to replace Michael Higdon is paying off handsomely with the Englishman on five goals already.
"I have always liked big Sutty," McCall said. "I was disappointed to lose him but I understood totally when he left. Once I realised he was going to be up for grabs and we lost Higdon, it was a no-brainer for me.
"He is good in the dressing room, he is popular, and if you give him the service, he will score goals. And not only that, he is a handful. Everyone looked at big Higdon as a handful and Sutty is the same, and has a bit more mobility if I'm honest.
"I'm delighted for Sutty, he is a really good professional, he works hard at everything he does and he is getting his rewards."
McCall thought Motherwell just needed to increase the tempo slightly after the first half, and explained why he took James McFadden off at the break.
"Obviously he played 90 minutes on Wednesday," McCall said. "I thought with his goal his confidence would be high. Iain Vigurs pulled out of training on Thursday with a thigh strain.
"He passed a late fitness test but I had already made my mind up, because I thought he would be out completely, that Faddy would start. His hamstring tightened up, which is nothing too serious, after playing 90 minutes and 45 in close proximity.
"We wanted Faddy to come into the middle and cause problems, which I think he did at times. But even before the game I said 'Faddy, just give us 45 minutes, an hour' and now we have someone like Ainsworth to come on."
County manager Derek Adams was happy with his side's football but bemoaned their inability to deal with crosses in the second half.
"I thought we played very well in the game as a whole," he said. "The first half we created openings and didn't really look under any threat. I know Brown made a really good save but Richard Brittain had a great chance to make it 2-0 just before half-time.
"The second half we didn't deal with the cross into the box. From that point of view, disappointing, but overall it was a good performance from us.
"I thought we were good in possession and I'm delighted De Leeuw has got another goal, but we haven't dealt well with Sutton all day and that was a major problem."
Sutton's original marker, Brian McLean, went off in the 37th minute with concussion and blurred vision following an accidental collision with the forward.
"Brian was a major miss for us because he was doing well," Adams said. "That maybe did unsettle us. We didn't want to make the change because we knew the threat Motherwell had by playing the ball long to the strikers."