The present invention is a trowel having a blade with a rounded side edge, a straight side edge, and a notched edge between the rounded side edge and the straight side edge. The trowel may include a handle disposed opposite the notched edge and substantially parallel to the straight side edge, aligned with the plane of the blade. The blade may be made of a thin or flexible material, allowing the blade to be slightly deformed during use to create a consistent layer of adhesive. The rounded edge may be of a relatively smaller radius, allowing for a wider, shorter blade. In other embodiments, the rounded edge may be of a relatively bigger radius, allowing for a narrower, taller blade. The notched edge may be square notches, v-notches, u-notches, or other notch shapes according to user preference.