TO LAY ON WITH A TROWEL, verb. phr. (old).1. To flatter or exaggerate grossly; TO BUTTER (q.v.). Also (2) to lie (RAY); and (3) to use powder, paint, or the like, without stint.
1600. SHAKESPEARE, As You Like It, i. 2. Well said: that was LAID ON WITH A TROWEL.
1694. CONGREVE, The Double Dealer, iii. 10. Paints, dye say? Why she LAYS IT ON WITH A TROWEL has a great beard that bristles through it, and makes her look as if she were plastered with lime and hair.