You may boil the split pea with water instead of milk. My mom always uses milk so I do too.
Make sure the split pea is not too dry when done cooking. If dry, you may need to add milk when pureeing. However, do not add too much milk as the cooking time will be longer to dry up the added milk.
Use a thick bottomed or non-stick pan for ease of cooking and avoid burnout.
As the puree thickens on stove, the halva needs to be stirred consistently to achieve a smooth texture.
Few drops of rose-water is a delightful option to add a light rose flavor to the barfi.