With accent marks:
Ка́шу ма́слом не испо́ртишь.
You can't spoil the porridge with butter.
From time immemorial, porridge was loved and respected in Russia. It was cooked from wheat, buckwheat, oats, etc. To make it tastier, people added more butter.
This Russian proverb is used to say that something good can not be bad even in large quantities.
Other Russian proverbs
Do not dig a hole for another one, you will fall into it yourself.
A titmouse in hands is better than a crane in the sky.
Without labor, you can not even catch a fish in the pond.
Not everything that glitters is gold.
There are no friends for taste and color.
Each sandpiper praises its swamp.
Who is talking about what, and a lousy one about the bath.
Do not chop the branch you sit on