In a large saucepan heat oil over medium heat

Add onion and seasonings and cook, stirring occasionally, until onion is tender and golden

Add tomatoes and tomato paste

Stir and simmer for 10 minutes

In a small bowl whisk together the flour and 1/4 cup of the chicken broth

Stir into tomato mixture until well blended

Add the remaining broth

Simmer for 30 minutes, stirring frequently

Puree with an immersion blender until smooth

Add the Splenda and evaporated milk

Heat through