Cook, stirring, for two to three minutes until pasty.
With one hand, pour the broth in a thin stream while you stir with the other hand. Cook, stirring, until the roux and broth have blended together and the mixture has thickened.
Stir in the pepper and add more salt, if needed.
Add the potato and carrot cubes. Set the heat to LOW, cover the pot and simmer for 10 minutes.
Add the clams wait until the contents of the pot are boiling gently.
Turn off the heat, pour in the heavy cream and stir.