  We explore General Relativity solutions with stealth scalar hair in general
quadratic higher-order scalar-tensor theories. Adopting the assumption that the
scalar field has a constant kinetic term, we derive in a fully covariant manner
a set of conditions under which the Euler-Lagrange equations allow General
Relativity solutions as exact solutions in the presence of a general matter
component minimally coupled to gravity. The scalar field possesses a nontrivial
profile, which can be obtained by integrating the condition of constant kinetic
term for each metric solution. We demonstrate the construction of the scalar
field profile for several cases including the Kerr-Newman-de Sitter spacetime
as a general black hole solution characterized by mass, charge, and angular
momentum in the presence of a cosmological constant. We also show that
asymptotically anti-de Sitter spacetimes cannot support nontrivial scalar hair.
