Assuming a runway of infinite length, the power only has to be reduced until the aircraft descends slowly, and eventually it ought to touch down nicely as long as the speed is dead right
Yes, bare frozen lakes are good for this. There is a power setting which can be flown to get you to exactly CLmax, and hold you there. This will give you a landing which the the opposite of a glide approach. You can spend as long as you want in the flare. Obviously this is not normally done over the ground, as you'll run out, and there is a risk of touching down with a bit of drift. It is not good to sustain this in a floatplane, the plane will become very difficult to control. You can use this technique to get yourself to the surface safely when you cannot judge your height, but once you touch at all, it's either power off and land, or power full, and go around.
The floatplane glassy water landing is a variation of this, though a definite descent rate is important, 100 to 200 FPM does it. It takes a lot of nerve to descend until you contact while holding everything still. This may also have to be done when landing skis on unbroken snow, but that is high risk flying. You don't do that just for fun - it's not! It can be done on wheels too, but you get a pretty hard landing out of it.
In my flying boat the power on landing is entirely possible, because flying boats land quite differently to floatplanes. With just the right wind and water conditions once, I found a power setting at which I could fly, flare, touch down, plane on the step, takeoff again, fly, flare...... all without changing the power setting at all. The whole flight was in [water] effect, and it was a delicate management of drag.
I'll entertain myself doing this in the 150 on the ice, though some caution is required, as it is possible to bang the tail tiedown ring first if one is not cautious. I can go along for miles touching alternate main wheels, or "flying" with one main on, and the other off (you have to add a bit of power for that, to compensate the drag of the deflected ailerons.
