Plotting 2D gaussian distribution in 3D

So I'm wanting to see in 3D the 2D guassian distribution with the pdf in the 3rd dimension. Hopefully this makes sense...

Anyway I'm trying something simple for R1n = 2x100 matrix containing 100 samples and 2 dimensions

    [X,Y]=meshgrid(R1n(1,:),R1n(2,:)); %form x-y plane
    Z=peaks(X,Y);
    plot3(X,Y,Z);

but am not even coming close? Any advice?