Where does “piirakkalasta” come from?

piirakkalasta (Finnish) comes from Finnish piirakka, from Russian пиро́г, from Old East Slavic пирогъ, from Proto-Slavic pirogъ, from Proto-Slavic pirъ — fest; party.

piirakkalasta (Finnish): pie server

Definitions

pie server

Ancestry of “piirakkalasta”, step by step

piirakkalasta traces back through two separate lines of ancestry.

via Finnish piirakka

Step	Language	Word	Meaning
1	Finnish	piirakka	pie; pierogi, pirog; pasty
2	Russian	пиро́г	pie
3	Old East Slavic	пирогъ	—
4	Proto-Slavic	pirogъ	type of pie?
5	Proto-Slavic	pirъ	fest; party

via Finnish lasta

Step	Language	Word	Meaning
1	Finnish	lasta	splint; spatula, scraper; Synonym of paistinlasta
2	Proto-Finnic	lasta	shake, splint, slat

Every word from Proto-Slavic pirъ →Every word from Proto-Slavic pirogъ →Every word from Old East Slavic пирогъ →