Raise chickens, that’s what.

In a new blog post, the Microsoft (MSFT) co-founder and philanthropist writes that raising chickens is probably the easiest and cheapest way to make money as well as to assure a food supply if you are poor and have access to land.

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Clearly, he’s done the research. First, chickens are relatively cheap to maintain. Some breeds can live off what they eat off the ground, he explains, although augmenting that is probably a good idea. As for shelter, hens need just a rudimentary structure to protect their nests and eggs.

Farmers who start with five hens and borrow a neighbor’s rooster to fertilize them can end up with 40 chicks within approximately three months, or a quarter of the year. In West Africa, those chicks can sell for $5 each. Thus, farmers could earn as much as $200 per quarter, or $1,000 per year, in income. That’s not much, but it’s a step up from the extreme poverty line of $700 a year, Gates wrote.

Additionally, eggs are also a protein-rich food source.

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Finally, because chickens tend to stick close to home, a parent caring for his or her children at home can also tend the flock.

Gates also offered a way to help. If you read the blog post, watch the video, and answer a question, Gates will donate—on your behalf—a flock of chickens to a poor family. The poultry logistics will be handled by Heifer International, a non-profit group dedicated to providing livestock and training to impoverished people around the world.

This post comes a day after Melinda Gates wrote her own ode to chickens. The couple co-chair the Bill & Melinda Gates Foundation, which spends billions each year combating disease, hunger, and poverty.

This story was updated at 4:50 p.m. EDT to include a link to Heifer International.