Isekai Tensei Slum-gai kara no Nariagari: Saishu ya Ryou wo Shite Gohan Tabete Slow Life Surunda

At the age of 6, Ed, a boy suddenly recalls that he is a reincarnated individual from modern Japan. However, his current life unfolds in the slums of another world!
Struggling with a poverty-stricken existence in his daily life, he shares his living space with and eats with his childhood friend, a girl named Miinya. Their daily fare consists mainly of 'boiled beans.' Ed, drawing upon his knowledge from modern Japan, discovers edible wild plants and leaves suitable for making tea to improve their dietary situation.
In pursuit of a slow life, Ed's life of gathering and hunting begins!

(Source: Futabasha, translated)