Place the garlic and salt in a mortar and grind with the pestle until a course, grainy paste is formed. Scrape into a large bowl.
Add the beans, olive oil, and lemon juice. Use a potato masher to create a thick, smooth, creamy spread.
Scrape into a serving bowl or small plates and dust with the rosemary and sage before serving.
If you don’t have a mortar and pestle, process the garlic, salt, beans, and lemon juice in a food processor fitted with the chopping blade until fairly smooth. Scrape down the inside of the canister, then add the oil in a thin stream through the feed tube as the machine runs to create a rich spread.
If you’ve refrigerated the spread, let it come back to room temperature on the counter for up to 1 hour before serving for the best flavor.
