Building consistency in your iron play requires compressing the golf ball – hitting down and through with a slight shaft lean rather than trying to lift the ball into the air.
A great drill to find this feeling is to hold an alignment stick against the shaft of the club with the stick extending past the grip and up against your left side (for the right-handed player).
As you rotate away from the golf ball, the alignment stick will show where the club travels. As you return in the downswing, the stick should lead, with the head of the club following slightly behind, producing a little shaft lean and a solid striking position.
Take a few practice swings with this at a slow speed then remove the stick and see how your ball striking improves.