In resealable plastic food-storage bag, place cheeses and flour. Coat cheese with flour by shaking cheese and flour.
Add some garlic to the pot (you can use a fondue pot with this). Add wine. Simmer (don't let it boil). Add lemon juice.
Add cheese mixture as you stir with a whisk over low heat, until melted. Stir in sherry.
Keep warm over simmer setting. If prepared in saucepan or skillet, pour into a fondue pot or heatproof serving bowl and keep warm.
Spear bread and fruit with forks or skewers (any supermarket should carry wooden skewers).