Preheat oven to 325°. In a small bowl, whisk together cumin, paprika, garlic, coriander, and 1 1/2 tsp. salt. Rub roast with 1 tbsp. oil and pat spice mixture all over roast.
In a dutch oven or other heavy 5- to 6-qt. pot, heat 1 tbsp. oil over medium heat. Brown roast on all sides, about 4 minutes per side, adding another 1/2 tbsp. oil halfway through browning.
Transfer roast to a plate and wipe pot clean with a paper towel. Add 1/2 tbsp. oil to pot, put roast back in pot, and roast until a meat thermometer inserted in the thickest part registers 135°, about 50 minutes.
Transfer roast to a rimmed cutting board and tent with foil. Add remaining 1 tbsp. oil and the flour to pot and, over medium heat, whisk 1 to 2 minutes to cook flour. Whisk in tomato paste. Slowly whisk in beef broth and bring to a simmer. Cook gravy until thickened slightly, whisking frequently, 7 to 9 minutes. Season to taste with salt.
Slice roast thinly and serve with pan gravy.
*Available at Whole Foods Markets and by request from your butcher.