Shiva Purana

siva.sh/siva-purana/rudra-samhita/14/51

मुद्गानां पूजने देवः शिवो यच्छति वै सुखम् ।। प्रस्थानां सप्तकेनैव प्रस्थार्द्धेनाथवा पुनः ।।५१।।

sanskrit

In the worship with mudga (green gram/lentils), Lord Shiva indeed bestows happiness. (One should offer) seven prasthas, or alternatively, half a prastha, once again.

english translation

mudgAnAM pUjane devaH zivo yacchati vai sukham || prasthAnAM saptakenaiva prasthArddhenAthavA punaH ||51||

hk transliteration by Sanscript