Plot3D[1/8 (6 Exp[-((2/3 Abs[x] - 1)^2 + (2/3 y)^2) -
1/3 (2/3 y + 1/2)^3] +
2/3 Exp[-2.818^11 ((Abs[2/3 x] - 1)^2 + (2/3 y)^2)^2] +
2/3 y - (2/3 x)^4), {x, -3, 3}, {y, -3, 3}, PlotRange -> {-2, 1},
BoxRatios -> {6, 6, 4}, PlotPoints -> {100, 100},
ColorFunctionScaling -> False,
ColorFunction ->
Function[{x, y, z},
If[Sqrt[(Abs[x] - 3/2)^2 + y^2] < 0.45,
Blend[{Pink, LightPink}, 0.5], LightPink]], Mesh -> None]