Are you sure it is laquer? It could be shelac. Shelac is easy to test for. Alcohol will disolve it. Alcohol will not touch laquer.

All the trim in our house is shellac, and some is crackled, too. I've been using denatured alcohol and fine steel wool to remove it. Sometimes it takes a bit of elbow grease, but it's worth it. I think if you just put something on top of it you won't get the effect you want. And if you ever decide to paint, don't paint right on top of the shellac. Eventually you'll see that cracking in the paint, too.

Test with denatured alcohol to see if the finish is shellac or lacquer.
Test with lacquer thinner to make sure the finish is lacquer and not any type of varnish.
Lacquer is the same product, made by dissolving nitrocellulose in solvents. I have not seen lacquer made by minwax. Most of their products are polyurethane.
If the finish is lacquer it must be cleaned of any surface grime before another coat is applied or the grime will be embedded into the finish.
Deft clear wood finish is a nitrocellulose lacquer product that is relatively easy to apply with a brush. The gloss is harder and can be rubbed with steel wool (#0000) to any desired semi-gloss level.

Hmmm, I thought I was dealing with lacquer but after rubbing a section with denatured alcohol I see that it wore away the finish.

So if I am dealing with Shellac, what is the best way to restore it? Do I need to remove all of the existing finish before refinishing or is there a way to restore the shellac finish?

thanks again.

Shellac can be restored by gently cleaning with a damp rag 9water will soften and destroy shellac). Wipe with paint thinner to remove any remaining grease and grime, than paint with denature alcohol. The old shellac will dissolve and smooth out. If the shellac is worn to thin you can apply another layer.
Shellac flakes are available from Master, and are dissolved in either denatured alcohol or Behkol. Constantines has both.
Shellac takes some practice to apply since it dries nearly instantly. A badger hair brush works very well.

Here is a link that might be useful: shellac flakes