Heat olive oil in a small skillet over medium heat; add garlic and fresh rosemary leaves. Cook until toasted (1-2 minutes). Transfer toasted garlic and beans to a food processor with fresh lemon juice and water. Purée until smooth; drizzle with additional oil before serving, if desired. Eat with 1 ounce pita chips. Refrigerate remaining dip in airtight container up to 3 days.