Revākhaṇḍa ascribed to the Vāyupurāṇa (RKV) 182.54

182.54

suvarṇaśṛṅgīṃ kapilāṃ payasvinīṃ sādhvīṃ suśīlāṃ taruṇīṃ savatsām /
dattvā dvije sarvavratopapanne phalaṃ ca yatsyāttadihaiva nūnam //

The fruit that one would obtain by giving to a Brahmin endowed with all vows
a brown cow with golden horns, yielding milk, gentle, of good nature, youthful, with her calf—that very fruit is certainly attained right here.