import iris
import matplotlib.pyplot as plt
import cartopy.crs as ccrs
import iris.plot as iplt

lat_plot_deg = [45, 40]
lon_plot_deg = [0, 5]
values = [[0, 0], [0, 0]]
ax = plt.axes(projection = ccrs.EckertIII())
lat_coord = iris.coords.DimCoord(lat_plot_deg, standard_name = "latitude")
lon_coord = iris.coords.DimCoord(lon_plot_deg, standard_name = "longitude")
new_cube = iris.cube.Cube(values, dim_coords_and_dims = [(lat_coord, 0), (lon_coord, 1)])
print("Before.")
cf = iplt.contourf(new_cube)
print("After.")