In food processor, chop garlic. Break mushrooms in half, drop in processor and process until coarsely chopped. Melt butter in frying pan over medium-high heat. Add garlic, onion, mushrooms, salt, thyme, and pepper. Cool, stirring occasionally, until most liquid has evaporated.
Process almonds until coarsely chopped.
Remove 2 Tablespoons nuts and set aside. Process remaining nuts to form a paste. Pour oil down feed tube and process until creamy. Add mushroom mixture and process until pate is smooth. Add reserved nuts and blend with two on-off bursts.