Combine the cauliflower and stock in a large pot.

Bring to a boil, uncovered and cook until there is almost no liquid left and the cauliflower is just beginning to caramelize (this is key for a good texture – too much liquid results in a runny puree), about 30 minutes on medium-high heat.

Meanwhile, brown the butter. Add the butter to a small pan or pot with a light color bottom (this will allow you to see when the butter solids have turned golden). Cook over medium heat until the butter smells nutty and the solids in the butter have turned a light golden color. Add sage leaves and continue to cook until the butter is a medium golden color and the leaves are crisp. Remove leaves to a paper towel lined plate and sprinkle with a bit of salt. Remove butter from heat and set aside.

Using an immersion blender, puree the now soft cauliflower until completely smooth. You can also transfer everything to a traditional blender and puree. Add in all but 2 tablespoons of browned butter, being sure to stir the butter well to incorporate all the golden brown solids. Season to taste with salt and pepper. Transfer to a serving bowl and drizzle with remaining browned butter. Scatter sage over top.