Plotting x and y values with result as color / heatmap

Basically I have some x and y values. Each set of x and y values have a given value that corresponds to them. I am not sure a general seaborn heatmap would suffice when wanting to do that (I might be mistaken), so what to do ?

I would like it to look something like this (including bins, so that it's a more "smooth" colored surface, and not just a lot of different colored dots all around):

EDIT: So I'll try to explain better.

Let's say I have something like this:

import numpy as np 

nx = 3
ny = 5

x = np.linspace(0.1, 1, nx) 
y = np.linspace(1, 11, ny) 

x_bc = x[:, np.newaxis]
y_bc = y[np.newaxis, :]
z = x_bc * y_bc

The output of z is then every combination of x and y, i.e.:

[[  0.1     0.35    0.6     0.85    1.1  ]
[  0.55    1.925   3.3     4.675   6.05 ]
[  1.      3.5     6.      8.5    11.   ]]

So in this case I have 3x5 z-values, i.e. what should be the colors in the plot, and those values come from two lists (x and y) that has length 3 and 5 respectively. That is pretty much what I would like to plot.