Preheat oven to 450°F with cast iron pan inside. In a medium bowl, toss fennel and garlic cloves with a drizzle of olive oil. Sprinkle with salt and pepper. Roast, stirring once, until softened and lightly browned, about 12 minutes.

Meanwhile, heat another dry cast iron skillet over medium heat. Scatter almonds and toast until lightly brown, stirring frequently, about 5 minutes.

Let fennel and almonds cool slightly.

Using a food processor, grind almonds and nutritional yeast into a fine meal. Add roasted fennel, green fennel fronds, garlic, 2 tablespoons olive oil, avocado oil, and lemon juice and pulse until a puree forms. Add more olive oil and continue pulsing to reach a smooth consistency. Season with salt, if needed, and pulse quickly to combine.

Use right away or refrigerate for up to 3 days.