Dig a hole
Put something metal in it that's thick and has a hook
Fill hole with concrete
Anchor bike to thick metal hook thingy.
i use the bike lock that can only be cut with a plasma cutter, weighs a good 40 lbs. Thats around my front wheel anchored to the ground. Theres also a cover over my bike every minute im not using it. Out of sight out of mind. Oh and insurance lol