Where does “Lasanen” come from?

Lasanen (Finnish) comes from Finnish -nen, from Finnish -inen, from Finnish -uus, from Proto-Finnic -uc — -ness, -hood.

Ancestry of “Lasanen”, step by step

Step	Language	Word	Meaning
1	Finnish	-nen	Forms diminutives nouns or terms expressing...
2	Finnish	-inen	-like, -ous, -y; -en; Creates adjectives from...
3	Finnish	-uus	Forms nouns from adjectives, expressing a quality
4	Proto-Finnic	-uc	-ness, -hood