Preheat oven to 350 degrees F.
In a large saucepan over medium-high heat, bring the chicken broth or broth mixture to a simmer; reduce heat to low and let the broth simmer until ready to use.
In a large oven-proof pot (cast-iron Dutch oven) works well for this) over medium-low heat, heat vegetable oil until hot. Add onion and saute, stirring constantly, approximately 5 minutes until onions becomes translucent but not brown. Add garlic and jalapeno chile pepper, stirring constantly until soft.
Add rice, stirring constantly, until the rice just begins to brown. The rice will go from white to translucent and back to white again before it begins to brown. Once the rice is evenly browned, remove the pot from the heat and season salt and pepper to taste. Slowly and carefully add the hot chicken broth, tomatoes, and tomato paste, stirring to mix well.
Cover the pot and place in the preheated oven for 20 minutes. If after 20 minutes, the water has not been absorbed and the rice is not soft, place the pot back in the oven and continue to cook for another 5 minutes.
When the rice is done cooking, remove from the oven and let stand, covered, for at least 5 minutes to allow the rice to set.
You will need an extra 1/2 to 1 cup of liquid if you are going to cook this rice on the stove top.
To cook on the stove top, follow the above recipe except continue to cook on the stove top and add more liquid as needed.
Spanish Rice Recipe: https://whatscookingamerica.net/cynthiapineda/spanishrice.htm