In a large mixing bowl, combine all-purpose flour, sugar, yeast, and salt. Gradually pour in warm water and mix until a dough begins to form. Knead the mixture until it becomes smooth and elastic, about 8-10 minutes.

Cover the dough with a clean kitchen towel and place it in a warm area. Let it rise for 1-2 hours, until it doubles in size.

Once risen, gently punch down the dough to release air. Divide it into two equal portions. Color one half with black food coloring and the other with red.

On a lightly floured surface, roll out each portion of colored dough separately.

Layer the red dough atop the black dough and twist them together gently to form a loaf shape.

Allow the newly shaped loaf to rise again for about 30 minutes, covered with a towel.

Preheat your oven to 350°F (175°C). Place the dough in the oven and bake for approximately 30 minutes.

Once baked, remove the bread from the oven and let it cool on a wire rack before slicing.