In a medium-size saucepan, heat butter and olive oil over medium heat until butter is melted. Add the flour and whisk until smooth. Cook flour mixture for 1 minute, stirring frequently.
Add the spices and brown sugar and cook for 30 more seconds, until fragrant.
Add chicken broth, vinegar and tomato paste and whisk until well combined. Bring to a simmer and cook for 4-5 minutes until sauce is thickened and bubbly.
Notes
See Café Tips above in post for how to store this sauce as well as lots of more detailed instructions and recipe tips.