Cut off the tips of the head of garlic and drizzle with 1/2 tablespoon of the olive oil. Wrap the garlic in aluminum foil and place on a baking sheet in the oven. Roast for about 40 minutes.
Meanwhile, place potatoes in a medium pot with cold water and bring to a boil. Reduce heat to a simmer and cook potatoes for about 30 minutes until fork tender.
Drain potatoes and place in a large bowl.
Add the remaining 1/2 tablespoon of olive oil to a small skillet over medium-high heat.
Once hot, add the sage and pan-fry for about 1 minute until aromatic and starting to crisp.
Add the fried sage to the potatoes.
At this point the garlic should be roasted. Remove from oven and let cool until you can handle it.
Squeeze the roasted garlic cloves out into the bowl with the potatoes and sage.
Add the Voskos Greek Yogurt and salt & pepper to the bowl.
Mash with a potato masher until all ingredients are incorporated into the potatoes but the texture is still "chunky".