In a large pot over medium-high heat, add 2 tablespoons butter and when melted, throw in spinach. Stir every 30 seconds for about 2 minutes. Transfer to a colander to drain.
In a medium saucepan over medium heat, add remaining butter. When melted add onions and sauté for 1 ½ minutes. Add red peppers and do the same. Add garlic and sauté for 1 minute. Add flour and whish until ingredients are well coated. Add cream cheese; stir until blend inches Whisk in half-and-half a little at first and when sauce is very thick, pour the rest.
Reduce heat to medium-low and season with freshly black pepper, sea salt, nutmeg, cayenne pepper and hot sauce. Taste and adjust if necessary. Add drained spinach, stir until well incorporated and when heated through, remove from heat and serve immediately.