Pre heat broiler and set top rack down to the second position.
Trim 1 large fennel bulb from fronds and stems and cut into 1" dice and transfer to aluminium foil lined flat sheet. Roast under the broiler for 10-15 minutes or until the edges are begining to char. Reserve trimmed fennel fronds for serving.
When the fennel is nicely charred, melt 1 tbsp butter in a medium sauce pan over medium high heat and add 2 large shallots thinly sliced, to the melted butter and sauté stirring often until the shallots soften, about 5-6 minutes.
Grate in 1 clove garlic and add 1 tsp fennel seeds and continue to stir for another minute or until the garlic becomes fragrant.
Add charred fennel to shallot, garlic mixture, stir to combine, then add 3 cups chicken or vegetable stock Bring to a boil, reduce to a simmer, then cover with a lid and cook until very tender, about 15 minutes.
Remove from heat, add the juice of 1/2 of a lemon and blend until very smooth with an immersion blender. Stir in 1/4 cup heavy cream and set aside until ready to serve.
