Note: This recipe works best if you measure everything ahead of time and set it beside the stove. With everything ready to go, the recipe goes pretty quickly.
Steam the cauliflower according to your preferred method (see here for tips on using the Instant Pot). You can slice the cauliflower into “steaks” or just use the florets. (Note: As you can see in the photos, I sliced my whole head of cauliflower into two large “steaks” and then chopped the remaining cauliflower into florets.) Toss lemon slices and garlic with sugar. Set aside.
Place 1 cup flour in a shallow baking dish. Add salt and black pepper and stir to combine.
Heat a large skillet or saute pan over medium heat. (Note: You’ll want a pan that can hold all of the cauliflower, so it’s probably the largest one you have.)
Add 2 Tablespoons oil to the heated pan and swirl to coat the bottom of the pan.
Working quickly, dredge each piece of cauliflower in flour, shake off the excess, and place the cauliflower in the hot pan.
Cook on both sides until deep golden brown and cooked through, 3 to 5 minutes total. Set cauliflower aside and return pan to heat.
Add 1 Tablespoon olive oil to heated pan and then lemon slices and garlic.
Saute until garlic is fragrant and lemons are starting to turn golden in spots, 1 to 2 minutes (watch it closely and remove it from heat if the garlic starts to turn brown).
Pour charred lemons and garlic back into the bowl they were marinating in and return pan to heat.
Add shallots and oregano to heated pan.
Cook until shallots are tender, ~1 minute.
Add 1 Tablespoon flour and stir until no dry spots of flour remain.
Add white wine and broth to pan, scraping up any browned bits on the bottom of the pan.
Increase heat to bring sauce to a simmer.
Simmer until sauce reduces by half, about 5 minutes.
Remove pan from heat and whisk in butter and capers until butter melts.
Return cauliflower florets to pan and gently spoon sauce over top. Stir in lemons and garlic.
Top with parsley.
Serve over pasta or rice.