Cut the roast beef into strips, add the water for the rice. As soon as it boils, add rice. I use parboiled rice, which only needs to cook for 10 minutes, which works well with the sauce in terms of time.
For the sauce, heat the butter in a saucepan and sweat the flour in it. Add the cream while stirring. Stir in tomato paste. Season to taste with salt and pepper. Add the roast beef and heat.
If the sauce is too creamy for you, you can easily make it more liquid with milk, then add some seasoning if necessary.
Arrange the rice in a circle on the plate, powder with paprika, put the roast beef cream sauce in the center, refine with pieces of tomato.