A new method for constructing triangular patches is presented. A triangular patch that interpolates given boundary curves and cross-boundary slopes is formed by blending three traditional side-vertex interpolation operators (Nielson, 1979) with a new, interior interpolation operator. The new operator is the solution of an interpolation process that interpolates both the interior and the boundary of the triangular domain. The interior interpolation operator has better approximation precision on the interior of the triangle than the side-vertex operators. The constructed triangular patch reproduces polynomial surfaces of degree four. Comparison results of the new method with the side-vertex method (Nielson, 1979) are included.