An authentic Spanish rice recipe is available from the Food Network's website. This recipe calls for lard, long grain rice, tomatoes, chicken broth and onions.
Place 1 tablespoon of lard or solid vegetable shortening in a saucepan over a burner, and turn it to medium-high heat. Once the lard melts, add 1 1/2 cups of long grain rice. Stir the rice, and cook it until the grains start to brown. Add 1/4 of a chopped onion and 2 cloves of minced garlic to the mixture, and stir. Pour 2 whole tomatoes and 1/4 cup of liquid from the 15-ounce can of tomatoes along with 3/4 cup of chicken broth into the saucepan. Once the mixture starts to boil, reduce the burner to medium-low heat, and cover the saucepan. Allow the rice to simmer for up to 30 minutes, adding more chicken broth as needed.
Another authentic recipe starts by toasting 2 cups of medium white rice in 2 tablespoons of olive oil heated in a large skillet at medium-high heat. Add 1 chopped onion and 1 minced garlic clove to the rice, and cook until the onion turns translucent. In a separate pot, simmer 3 cups of chicken stock with 1 tablespoon of tomato paste, 1 pinch of oregano and 1 teaspoon of salt. Add the rice to the chicken stock, and simmer covered for 15 to 25 minutes.