How can you create a perfect homozygous cross?

Question

If i wanted all homozygous black cows (dominant)...is there another way to produce homozygous black cows apart from independent assortment or crossing homozygous black cows with heterozygous cows and hoping for the best?

Answer 1

The above answer is right.  Crossing an animal with the dominant phenotype agaisnt animal with the recessive phenotype, to determine if the dominat animal is heterzygous or homozygous, is called a "test cross".  

Answer 2

To determine if a given cow is homozygous black, mate it with a homozygous recessive bull (white?). If the cow is homozygous then it will always produce black offspring. If it is heterozygous then half the offspring will be white.

You can do the same with black bulls and white cows. Once you have identified homozygous individuals crossing them will always produce more homozygous black