Tallywell.

Black beans (cooked) vs Lentils (cooked)

Both count toward 30 plants a week.

Black beans (cooked)Lentils (cooked)
Protein · per 100 g8.9 g9.0 g
Fiber · per 100 g8.7 g7.9 g
Energy · per 100 g132 kcal116 kcal
Protein · per 100 kcal6.7 g7.8 g
To hit 30 g protein337 g · 445 kcal333 g · 387 kcal

Bold marks the better side of each row. "Per 100 kcal" answers the density question — which food delivers more protein for the energy it costs. Portion row is computed live from the same USDA base values shown on each food page.